Results revealed long, pointed teeth, and a bone forming the roof of the mouth and upper and lower jaws.
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Firstly the upper and lower jaws are wrenched apart in a move straight from the Saw films torture manual.
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Furthermore, the junction between the left and right lower jaws is well developed, giving the animal a bit of a chin.
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In the majority of whales studied, the second and third teeth of the orca's lower jaws were broken, a likely consequence of the drilling.
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They did an incredibly thorough intake, she says—bite x-rays, Panorex to get a full view of the upper and lower jaws, the works.
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They cut one open, discovered a package hidden underneath the bananas, and then probably had to spend a couple of minutes putting their lower jaws back into place.
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Furthermore, the pterosaur has surprisingly small eyes, and its dentition is "quite a mix, with a combination of fangs and miniscule teeth in each side of the lower jaws," Britt said.
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As noted in the new study, more than 65 percent of the whales studied exhibited moderate to extreme tooth wear in their lower jaws, mostly as a result of this chewing behavior.
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In all, it has 80 teeth on its lower jaws (including the four fangs), and 30 on its upper jaws, including eight little ones in the front and 22 medium teeth in the back.
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Such stunts strain the marine mammals' sensitive lower jaws in a way that can damage their hearing, injure joints and muscles and worsen other injuries caused by confinement within holding tanks where the dolphins are kept.
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The findings, announced on Wednesday, shed light on a species, called Gigantopithecus blacki, that has been shrouded in mystery because its fossil remains are so sparse - just a collection of teeth and remnants of several lower jaws.
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But, when Dr Geisler and his colleagues brought together the teeth from the animal's upper and lower jaws they found the result was a sieve that would have superbly served the task of filtering out small animals from water passing through them.
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It also includes lower jaws, catalogued as MOR 591-7-15-89-1. Both skull and lower jaws are nearly complete, lacking only the braincase and occipital region. MOR 591 is smaller than the holotype with a skull base length of about . Specimen MOR 571 includes a partial skull and lower jaws with associated ribs and vertebrae of an adult.
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A third specimen is MFSN 25161, a partial skull, lacking the lower jaws.
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The lower jaws have a length of . On the front two thirds of their length teeth are present. There are twelve pairs of teeth in both the upper and the lower jaws. The teeth are robust, sharp, pointed, and curving backwards.
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Blasisaurus also differs from Koutalisaurus by a downwardly bent front edge of the lower jaws.
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In C. hattini, the upper and lower jaws are similar to that of Cretoxyrhina mantelli. The jaws also resemble those of modern alopiids (thresher sharks) and lamnids. Limited fossil evidence suggests that the upper jaws extended over the lower jaws, giving Cretalamna a subterminal mouth.
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The anatomy of the teeth and lower jaws are similar to those of the extinct sperm whale genus, Orycterocetus.
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These gobies are generally under 10 centimeters long. They have tricuspid outer teeth on their upper and lower jaws.
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Restorations of the skull and head Europejara is a relatively small form with an estimated wingspan of two metres. The jaws are toothless and the lower jaws bear a large downwards pointing crest. The describers established three autapomorphies, unique derived traits. The crest on the lower jaws is curved to the back.
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Chicago & London.Watson, D. M. S. (1912). LXVII.—On some reptilian lower jaws. Journal of Natural History, 10(60), 573-587.
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Strong ligaments connecting the upper and lower jaws restrict the jaw gape. The strong adductor muscles can be asynchronously activated.
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The specific name, mini, refers to the small size of the specimens. Yulong is based on a syntype series of five specimens: HGM 41HIII-0107: an exceptionally well-preserved skeleton with a skull and lower jaws that is housed in the Henan Geological Museum, only lacking the skull and the neck base; HGM 41HIII-0108: a skull lacking the lower jaws; HGM 41HIII-0109: a partial skeleton with skull and lower jaws; HGM 41HIII-0110: a partial skull with lower jaws and some neck vertebrae; and HGM 41HIII-0111: a left ilium. Additional finds have been mentioned in the describing paper. One exceptionally preserved embryo (within an egg) is HGM 41HIII-0301, which came from a nest of 26 eggs.
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There are at least 27 teeth in each side of both the upper and lower jaws, which is a large amount.
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It consists of a partial skull with lower jaws, compressed on a slab and counterslab. Two elements of the hyoid are present also. The skull has been vertically crushed, the lower jaws horizontally. The specimen was prepared by Mercedes Llandres Serrano, and is part of the Las Hoyas collection of the Museo de las Ciencias de Castilla–La Mancha.
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It consists of a skull with lower jaws and four neck vertebrae. It was a possible subadult or, despite a smaller size, adult.
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Blochius was about 60 cm long and had a very slender elongated body, a narrow head with elongated upper and lower jaws and large eyes.
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Nanictidopids have enlarged canine teeth in their upper and lower jaws, while the teeth behind them are very small. Small bumps and ridges cover parts of the upper and lower jaws. The parietal region at the back of the skull forms a sagittal crest. The postorbital bones that make up the back of the eye sockets are very thin, and sometimes do not enclose the entire socket.
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The skull roof is relatively thick. Oblique grooves in the jaw joints caused the gape of the mouth to be widened when the lower jaws were opened. These jaws at the front are rather tall and wide. No teeth have been preserved in either the upper or lower jaws, but the size of its toothsockets proves that the third tooth of the lower jaw was enlarged.
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Newts share many of the characteristics of their salamander kin, Caudata, including semipermeable glandular skin, four equal-sized limbs, and a distinct tail. The newt's skin, however, is not as smooth as that of other salamanders. Aquatic larvae have true teeth on both upper and lower jaws, and external gills. They have the ability to regenerate limbs, eyes, spinal cords, hearts, intestines, and upper and lower jaws.
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One main characteristic of elasmobranch fishes is their ability to continually replace the teeth in their upper and lower jaws. Smooth dogfish differ from other sharks because of their 10 rows of flat, blunt teeth. The teeth in the upper and lower jaws are similar in size and are asymmetrical with rounded cusps. These teeth are used to crush and grind food, rather than bite it.
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The midline groove at the top of the lower jaws symphysis is deep. Furthermore, there is a density of 4.5 teeth per three centimeters of jaw edge.
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The mouth is large and protractile, and both upper and lower jaws have tiny teeth for eating fishes, worms, crustaceans, and other small aquatic animals at night.
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480 pp. . Neonates and juveniles often feed on lizards. Heat sensitive pits in the upper and lower jaws are used to help locate prey during nocturnal hunting.
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Like the upper jaws, the paired lower jaws of pterosaurs were very elongated. In advanced forms, they tended to be shorter than the upper cranium because the jaw joint was in a more forward position. The front lower jaw bones, the dentaries or ossa dentalia, were at the tip tightly fused into a central symphysis. This made the lower jaws function as a single connected whole, the mandible.
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Guimarotodon leiriensis is found in Kimmeridgian (Upper Jurassic) of Guimarota, Portugal. Classification is based on three lower jaws. The species name refers to the local town of Leiria.
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The holotype of Z. shepardi is IGM 100/1321, consisting of the posterior region of the skull and lower jaws with articulation with cervical vertebrae, forelimb elements and osteoderms.
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Males have a baggy vocal sac with a clear posterior flap. The upper and lower jaws are barred. The gular region is greyish in males but speckled in females.
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A horse can also suffer from an equine malocclusion where there is a misalignment between the upper and lower jaws. This can lead to a number of dental problems.
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They are able to replace their teeth simultaneously on the upper and lower jaws. Males are larger and more full- bodied than females. It grows to a length of SL.
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The lower jaws have a preserved length of twenty-three centimetres and an estimated original length of 255 millimetres. In their front parts the lower jaws are fused by a symphysis into a mandibula. The symphysis has a concave upper profile and features a large crest on the underside, pointing downwards for at least nine centimetres. The back edge of the crest is recurved; the curvature of the front edge cannot be exactly established because of damage.
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No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniform dark coloration Short abdomen and short caudal peduncle, close-set denticles on body.
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The skull has a length of thirty-eight millimetres. The snout is elongated and tapering. The lower jaws show an incipient crest. The specimen could not be more precisely determined than Pterodactyloidea.
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Blochius longirostris was similar to a swordfish. It could reach a length of about and had a very slender elongated body, a narrow head with elongated upper and lower jaws and large eyes.
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Restored skull Pterodaustro has a very elongated skull, up to long. The portion in front of the eye sockets comprises 85 percent of skull length. The long snout and lower jaws curve strongly upwards; the tangent at the point of the snout is perpendicular to that of the jaw joint. Pterodaustro has about a thousand bristle-like modified teeth in its lower jaws that might have been used to strain crustaceans, plankton, algae, and other small creatures from the water.
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Life restoration of Angistorhinus grandis Angistorhinus (meaning "narrow snout" or "hook snout") is an extinct genus of phytosaur known from the Late Triassic period of Texas and Wyoming, United States. It was first named by Mehl in 1913 and the type species is Angistorhinus grandis. Other species from Texas and Wyoming, A. alticephalus (Stovall and Wharton, 1936), A. gracilis (Mehl, 1915) and A. maximus (Mehl, 1928), are cospecific with the type species. Angistorhinus is known from the holotype UC 631, partial skull and lower jaws recovered from the Popo Agie Formation, Chugwater Group, Wyoming and from the associated paratype UM 531, a partial skull, TMM 31098-1, skull and lower jaws and ROM 7977, partial skull and lower jaws, recovered from the 'Pre-Tecovas Horizon' in the Dockum Group, Texas.
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Mammalian tooth counts are usually identical in the upper and lower jaws, but not always. For example, the aye-aye has a formula of , demonstrating the need for both upper and lower quadrant counts.
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These sockets do not vary significantly in size. The distance between the tooth sockets about equals their diameter. The midline ridge on the palate is high. A crest is present below the lower jaws.
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Skull of P. africanus. Proconsul africanus had a dental formula of 2.1.2.3 on both the upper and lower jaws. The molars of this species had thin enamel and there was a prominent molar cingula.
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Xiphiorhynchus is an extinct genus of prehistoric swordfish that lived from the Eocene until the Miocene. Unlike the modern swordfish, both the upper and lower jaws of Xiphiorhynchus were extended into blade-like points.
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An excess of these bone-eating cells contributes to the destruction of bone in the upper and lower jaws. A combination of bone loss and inflammation likely underlies the cyst-like growths characteristic of cherubism.
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In 2009, two front skulls and lower jaws of very young, perhaps newly hatched, individuals, specimens IGM 100/972 and IGM 100/974, were referred to Byronosaurus, after originally having been identified as Velociraptor exemplars.
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He also cannot run because doctors removed bones from his legs to use in reconstructing his upper and lower jaws. His first surgery was 19 hours long and he's since had two dozen reconstructive surgeries.
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Because of the sparse material, Phyllodon has often been tossed off as a dubious basal ornithopod of uncertain affinities. However, more material that might belong to this genus has been recovered from the original locality and described. Included in this material are over 120 more teeth from all parts of the jaw and four partial lower jaws with the teeth lost. Oliver Rauhut, who described the new material, tentatively identified the lower jaws as Phyllodon due to there being no other similar dinosaurs found at the locality.
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As in other ankylosaurs, thick triangular scutes projected from the postorbital bone, above and behind the eyes, as well as the jugal bone, below and behind the eyes. More typically for nodosaurids, leaf-shaped teeth lined both upper and lower jaws, used for cutting plant material. The front end of the skull is unknown, but there would have been a sharp bony ridge (tomium) at the end of both upper and lower jaws, as seen in other ankylosaurs. This ridge probably would have supported a keratinous beak.
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Related species (including several taxa formerly included within the genus) had crests on their lower jaws, so the same probably also applied to L. compressirostris.Unwin, D.M. (2006). The Pterosaurs: From Deep Time. Pi Press:New York, p. 106. .
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An exploded python skull with disarticulated upper and lower jaws. The quadrate bone (c) is particularly elongated in snakes, to facilitate cranial kinesis. Courtesy of the Peabody Museum of Natural History, Division of Vertebrate Zoology, Yale University.
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There is a unique combination of traits: the snout bears a crest; the front part of the snout is rounded; the front part of the lower jaws is rounded; the margins of the front tooth sockets diverge.
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Like most other Paleogene crocodyloids, Asiatosuchus has a generalized crocodilian skull that is triangular in shape when viewed from above. Asiatosuchus species have teeth in the upper jaw that completely overlap the teeth in the lower jaw, giving them overbites. An overbite is a primitive feature among crocodyloids because modern crocodiles have teeth in the upper and lower jaws that interlock with each other with little overlap. Asiatosuchus can be distinguished from other early crocodyloids by its extended mandibular symphysis, the region where the two halves of the lower jaws connect.
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Sometimes numbering more than fifty, these stones are occasionally found in the abdominal cavities of psittacosaurs, and may have been stored in a gizzard, as in modern birds. Unlike many other dinosaurs, psittacosaurs had akinetic skulls: that is to say, the upper and lower jaws each behaved as a single unit, without internal joints. The only joint was the jaw joint itself, and psittacosaurs could slide their lower jaws forward and backward on the joint, permitting a shearing action. Unlike most ceratopsians, their beaks did not form curved tips, but were instead rounded and flattened.
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The lower jaws were short, stout, and curved downward, possibly an adaptation for eating seeds. Jeholornis prima lacked teeth in their upper jaws, and had only three small teeth in their lower jaws, while J. palmapenis had a few teeth in the middle of the upper jaw (maxilla) but none in the front (premaxilla). The upper teeth of J. palmapenis seem to have been angled slightly forward as in some other basal avialans. The teeth in all three species were small, blunt and peg-like with no serrations.
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In the skull, it has a significantly longer rostrum (the front part of the skull) and diastema (the gap between the incisors and the molars). Furthermore, it has shorter molar rows in both the upper and lower jaws.
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The diet includes a range of small- to medium-sized birds and mammals. Neonates and juveniles often feed on lizards. Heat sensitive pits in the upper and lower jaws are used to help locate prey during nocturnal hunting.
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However, male dragonets can be differentiated from the goby by their very long dorsal fins, and females by their protruding lower jaws. The Draconettidae may be considered a sister family, whose members are very much alike, though rarely seen.
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The maxillary teeth are rather recurved. The lacrimal bone lacks a pneumatic channel. In the braincase the subotic recess is large. The tips of the lower jaws do not curve towards each other but touch at their inner sides.
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In the lower jaws, the bones of the front and back halves loosely articulated, permitting the jaws to bow outward and increasing the animal's gape.Paul, Gregory S. (1988). Predatory Dinosaurs of the World. 91 and Figure 4–5 (93).
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The symphysis of the lower jaws has at the midline of its front an odontoid, or tooth-like, process, formed by a confluence of the side ridges of the occlusal groove, in the top surface of the joint dentaries.
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Articulation surfaces for the lower jaws; the glenoids, are broad, shallow, and situated around the occlusal line of the upper cheek teeth. Both paroccipital processes are short and parietals are weakly developed. The basicranium, or occiput, is considered basal.
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Indraloris is known from isolated teeth and fragmentary lower jaws. The jaw is deep under the last premolars, but becomes shallower towards the front. The lower premolars are elongate. The lower molars are shorter and broader than those of Sivaladapis.
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Dellichthys trnskii, is a clingfish, the second species in the genus Dellichthys, recently discovered from intertidal and shallow coastal waters of New Zealand. Its length is between 11.9–46.0 mm. Snout broad and short. upper and lower jaws equal in length.
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The specific name, "fortis", means mighty. The binomial means "Mighty Iguana Colossus". Additional findings at the Doelling's Bowl site are currently on revision, compromising mostly juvenile material based on lower jaws and humerus. Other remains include a large femur and pubis.
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However, this was not reported in other geographic area where the isopod has been found in reared fish. Fish infected with adult parasites did not show serious pathology. Lesions were localized at the upper and lower jaws and the tongue.
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5388/196, consists of a partial pair of lower jaws with teeth. Other specimens include numerous lower jaw fragments, a single partial premaxilla and many isolated teeth. An isolated right parietal, PIN no. 5388/198, may also belong to Parasuminia.
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When the upper and lower jaws close together, the lamellae mesh together to allow the bill to be closed fully.Jenkin, P.M. "The Filter-Feeding and Food of Flamingoes (Phoenicopter)". Philosophical Transactions of the Royal Society of London. 240(674), 401-493.
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The upper and lower jaws are white. The fins are hyaline, becoming dark brown or grayish black at the margins. The maximum known length is 30 cm. Like other apteronotids, S. porcium generates a weak electric field for electrolocation and communication.
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From a distance melon-headed whales could also be confused with false killer whales (Pseudorca crassidens), but the much larger size– adult length–long slender body shape and relatively smaller dorsal fin of false killer whales should distinguish them from melon-headed whales. Stranded/post-mortem individuals can be easily identified by tooth number: melon-headed whales have 20 – 25 pairs of slender teeth (more similar to the teeth of smaller dolphins than other blackfish) in both the upper and lower jaws compared to 8–13 pairs of robust teeth in both the upper and lower jaws for pygmy killer whales.
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The maxillaries and premaxillaries in worm pearlfishes are joined by short connective fibers in the small mouth opening. Both the maxillaries and premaxillaries connected to the fish's skin, which creates a small mouth opening. Worm pearlfishes’ mouths are smaller and weaker than mouths of pearlfishes in other genera because they feed on soft, unresisting food in a confined space, as opposed to swift-moving, unconstrained prey. Their upper jaw is lined with an outside row of strong, curved teeth, and an inner row of conical teeth. Worm pearlfishes’ lower jaws contain one row of conical 20 teeth or more on their lower jaws.
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The head is moderately long, with a blunt snout and long, broadly arched jaws. There are 4-5 rows of teeth on the upper and lower jaws of the blind side, and 2-3 and 1 rows on upper and lower jaws respectively of the eyed side. The teeth are sharp and recurved, and better developed on the blind-side jaws. The body is notably deep compared to other Symphurus species. The origin of the dorsal fin is located above the eyes and contains 88-94 rays. The dorsal fin pterygiophores and neural spines have a 1-2-2-2-2 interdigitation pattern.
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Restoration Bakonydraco is based on holotype MTM Gyn/3, a nearly complete mandibula, a fusion of the lower jaws. Also assigned to it, as paratype, is MTM Gyn/4, 21: parts from another jaw's symphysis (the front parts, having fused into a single blade-like structure, of the two lower jaws); azhdarchid wing bones and neck vertebrae from the same area may also belong to it. The lower jaws are toothless and the two halves of the mandibula are frontally fused for about half of its overall length, forming a long, pointed section that is compressed side-to-side and also expanded vertically, giving it a somewhat spearhead- or arrowhead-like shape from the side. This expansion occurs both on the lower edge and on the top surface, where the most extreme point corresponds with a transverse ridge which separates the straight back half of the symphysis from the pointed end in the front.
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The teeth in the upper jaw are concentrated in the front part and spaced far apart; their number is uncertain. The lower jaws have been well preserved. They are long and their symphysis is short. Twelve teeth are present in the dentary.
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The dorsal fluke is typically slightly hooked. The beak is well-defined and of moderate length. There are 26 to 36 pairs of teeth in the upper and lower jaws.. The tucuxi has one of the largest known encephalization quotients among mammals.
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It bears ten teeth for a total of forty-two in the head as a whole. The lower jaws have a central forwards pointing odontoid process in front. Of the hyoid bone two first ceratobranchialia have been preserved, thin elongated fork-shaped elements.
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In the rear jaws, the teeth are far apart. In top view, the symphysis of the lower jaw dentaries is four times longer than wide. The branches of the lower jaws are long and narrow, twenty times longer than wide in top view.
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The unerupted teeth are triangular in lateral view, which is the typical tooth morphology in basal ornithischians. The characteristic chisel-like shape of the fully erupted teeth therefore resulted from tooth-to-tooth contact between the dentition of the upper and lower jaws.
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Pseudhesperosuchus is based on PVL 3830\. This specimen consists of a skull and lower jaws, most of the vertebral column, the shoulder girdle, and parts of the arms and legs. The genus was named by José Bonaparte in 1969. The type species is P. jachaleri.
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Many species are highly compressed laterally and translucent in life. These fish have villiform (brush-like) teeth on the upper and lower jaws. The snout is relatively short. The eyes are relatively large, with a diameter equal to or greater than the distance between nares.
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Rodrigues & Kellner established four autapomorphies of Ikrandraco machaerorhynchus (then Lonchodraco). A deep crest is present at the underside of the lower jaws. To the rear, the profile of this crest turns upwards. Behind this crest a depression is present at the underside of the jaws.
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The skull of Pterofiltrus is very elongated, with an estimated length of 208 millimetres. It has a smooth, slightly concave, upper profile lacking any bony crests. The lower jaws too are long, and without a keel. The describers established the presence of five diagnostic traits.
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The total number of teeth in the head is about 112. The teeth cover more than half of the skull length, at 55.8%. The front teeth differ in length. The symphysis of the lower jaws represent more than half of the mandibular length, at 58%.
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The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 161–177. . The skull in fishes is formed from a series of only loosely connected bones. Jawless fish and sharks only poses a cartilaginous endocranium, with both the upper and lower jaws being separate elements.
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Mouth slightly supraterminal, oblique, and continuous groove separating upper lip from maxillary. Numerous small sharp teeth confined to upper and lower jaws, absent on roof of mouth. Gill membranes extending forward, broadly joined to each other, and free from isthmus. Gill rakers 7-10.
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Loreal and tympanic regions are dark-brownish black, and upper and lower jaws have brownish bands alternating with light grey. Both fore and hind-limbs have dark-brownish cross bands. Ventral side is grey with variable-sized dark-brown specks; hands and feet are greyish.
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The teeth are placed in tooth rows which together have a fluted profile. The tooth rows of the upper jaws bear about eighteen to twenty teeth. Those of the lower jaws bear twenty-eight teeth. The teeth are small, leaf-shaped and transversely flattened.
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The specific name honours Mona Shahin, one of the founders of the Mansoura University Vertebrate Paleontology Center. The Mansourasaurus specimen described in 2018 is its holotype, MUVP 200, discovered in a layer of the Quseir Formation dating from the late Campanian, about seventy-three million years old. It consists of a partial skeleton with skull and lower jaws. It contains a fragment of the skull roof, a part of the lower braincase, the dentaries of the lower jaws, three neck vertebrae, two back vertebrae, eight ribs, the right scapula, the right coracoid, both humeri, a radius, a third metacarpal, three metatarsals, and parts of osteoderms.
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The holotype skull (TMM 43631-1) that would be named Calsoyasuchus was discovered in 1997 by members of an expedition composed of crews from Texas Memorial Museum of the University of Texas at Austin, the Museum of Comparative Zoology at Harvard University, and the Seba Dalkai Navajo Nation School. It was found in the middle third of the silty facies of the Kayenta Formation, near the Adeii Eechii Cliffs. The skull is missing the lower jaws, part of the palate, most of the suspensorium (the bones that make up the region where the upper and lower jaws articulate), and the occiput and braincase. Sutures between the skull bones are mostly fused.
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There are large pneumatic openings in the posterior mandible and the whole of the mandible is hollow and was likely air-filled (pneumatic). Caelestiventus is a heterodont, with three different tooth shapes - long fang-like spikes, large "leaf-shaped" blades, and tiny blades. There are two long, spike-shaped teeth near the front of each side of the lower jaws that were likely opposed by similar teeth at the tip of the skull snout (premaxilla). In the lower jaws, behind the fangs, there is a tooth gap (diastema) which is followed by 38 tiny teeth on each side of the lower jaw (mandibular ramus).
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Autapomorphies of Jiangchangnathus include: a convex top margin of the lower jaw; a large front branch of the jugal; and the first three pairs of teeth of the lower jaws pointing strongly forwards. Its describers found it to share several features with Scaphognathus, including a high front end of the lower jaws, a pear-shaped lower temporal fenestra with the broad end below and teeth in the maxilla of the upper jaw that have a space equal to that of three toothsockets between them. Additionally, undescribed fossils of a pterosaur referred to Jianchangnathus suggest that the color of its pycnofibers was brown.Li, Q., J.A. Clarke, K.-Q.
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Extensive but vague remains of the plumage have been preserved as well as a crop with seeds and a stomach with gastroliths. Eogranivora is a medium-sized basal ornithuromorph. The describing authors indicated a distinguishing combination of traits, in themselves not unique. Both upper and lower jaws are toothless.
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These may affect how the incisors wear. In severe cases, the horse's ability to graze may be affected. Horses also sometimes suffer from equine malocclusion where there is a misalignment between their upper and lower jaws. The curvature of the incisors may also vary from the normal, straight bite.
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Trichonotus species have jutting lower jaws, five soft rays, and single pelvic spines. In males, the anterior rays on their dorsal fins may be extended. Their lateral lines run along the middle flank. On the back end of the lateral line scales is a deep, V-shaped notch.
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Dyoplosaurus was named by William Parks in 1924, based on holotype ROM 784, a partial skeleton including parts of the skull and lower jaws. It was collected from the bottom 10 m of the Dinosaur Park Formation, near what is now the Red Deer River in Alberta, Canada.
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Turtles have rigid beaks and use their jaws to cut and chew food. Turtles appear to have lost their teeth about 150–200 million years ago. Their upper and lower jaws are instead covered by horny ridges. Carnivorous turtles usually have knife-sharp ridges for slicing through their prey.
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Restored skull of Pterodaustro Euctenochasmatians had very distinctive features in comparison to other pterosaurs, including the shape of their jaws, as well as their highly specialized teeth. These teeth are thought to have been used for filter- feeding, the genus Pterodaustro for example, had a long snout and its lower jaws curve strongly upwards, and the tangent at the point of the snout was perpendicular to that of the jaw joint. Pterodaustro has around a thousand baleen-like teeth in its lower jaws that might have been used to strain crustaceans, plankton, algae, and other small creatures from the water. The teeth of Pterodaustro are unique within pterosaurs, and no other discovered genera had this type of teeth.
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Until the more recent discovery of a new specimen, Biseridens was primarily known from fragmented skull and jaw material discovered in the 1990s in the upper part of the upper Xidagou Formation of Gansu, China. The specimen included an incomplete skull with the posterior portion of the left ramus of the lower jaw and the anterior part of the lower jaws including well-preserved teeth. The more recently discovered specimen includes a nearly complete skull (lacking the occiput) with lower jaws, found with a set of 14 articulated vertebrae. This new specimen was preserved in mudrock and also discovered in the upper part of Xidagou Formation in Dashankau, Yumen in the Gansu Province of China.
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The rest of the bony palate, unlike all other dinosaurs, is extended below the jaw line and would have pushed into the space between the toothless lower jaws. A beak (rhamphotheca) covered the edges of the upper and lower jaws and probably the palate, as proposed by Barsbold and Osborn. The discovery of nesting specimens of the related Citipati, with the same types of egg in the original Oviraptor specimen, showed that the eggs actually belonged to Oviraptor, not Protoceratops, and that the type specimen was likely brooding the eggs, not feeding on them. While this discovery did not rule out the possibility that Oviraptor included eggs in its diet, its exact feeding strategies remain unknown.
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Jeholosaurus was a small bipedal herbivore. Because the specimens are juvenile it is hard to ascertain the adult size. The holotype is long with a long tail, nearly half the length of the complete animal. The length of the skull is and the lower jaws of the mandible are each.
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Bowerbank estimated P. giganteus had a wingspan of about eight to nine feet. Rodrigues & Kellner established two autapomorphies of Lonchodraco giganteus. Below the front of the lower jaws a short blade-like crest is present. There is a density of about six tooth sockets per three centimetres of jaw edge.
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The humerus has less than half of the length of the second phalanx of the fourth (wing) finger. Additionally the fossils shows a combination of traits that is unique for the Ornithocheiroidea. The palate has a distinct ridge. The upper jaws each have eleven teeth and the lower jaws each ten.
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That year, first several ribs were uncovered and later part of the vertebral column. In October, close to some neck vertebrae a skull and lower jaws were discovered. From 5 June 1912 onwards more neck and trunk vertebrae were found. Initially it was thought that a single skeleton was being uncovered.
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The structure of the Hunter-Schreger bands is very similar to Laonastes. The root of the incisor is shortened. The cheek teeth are bilophodont, displaying two transverse ridges that are each slightly curved into a mild horseshoe shape. Cheek teeth have four roots on both the upper and lower jaws.
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The known material consists of a nearly complete skeleton, missing only the feet and tail, though the holotype consists only of upper and lower jaws found in a different part of the same fossil site. In terms of completeness, it is the best-known thylacinid outside of the only recently extinct thylacine.
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The quadratum reclines 150 degrees relative to the lower edge of the skull. The basisphenoid of the lower braincase lacks appending processes. The basisphenoid does not reach the space between the pteroids. The rear half of the lower edge of the symphysis of the lower jaws is thick, forming a slightly convex surface.
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The genus name is derived from Normannia, the Medieval Latin name for Normandy, and Greek gnathos, "jaw". The specific name honors Peter Wellnhofer. The genus is based on holotype Musée Géologique Cantonal de Lausanne 59'583, the left front portion of a skull and the associated, but not articulated to it, lower jaws.
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Morphological diversity of the jaws of Cretaceous Ammonoidea. Abhandlungen der Geologischen Bundesanstalt, Wien 57: 157–165.Tanabe, K., P. Trask, R. Ross & Y. Hikida (2008). Late Cretaceous octobrachiate coleoid lower jaws from the north Pacific regions. Journal of Paleontology 82(2): 398–408. Klug, C., G. Schweigert, D. Fuchs & G. Dietl (2010).
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He called the animal who left the tooth Diplotomodon horrificus. In 1866, dinosaur remains were discovered in a marl pit near Barnsboro, New Jersey, owned by the Wet Jersey Marl Company. The discovery included partial lower jaws with teeth, both humeri, the left femur, tibia, and fibula, and a large number of vertebrae.
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Gasparinisuchus is known only from two individuals. The holotype MOZ 1750 PV represented by partial skull and lower jaws with teeth and various associated postcranial skeleton including vertebrae and dermal plates which are currently missing. It was originally described by Gasparini (1982) and Gasparini et al. (1991) and referred to Peirosaurus torminni.
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The specific name honours Venier as discoverer. The holotype, MFSN 21545, was found in a layer of the Dolomia di Forni Formation dating from the middle to upper Norian. It consists of a partial skeleton with skull and lower jaws. The skeleton is not articulated but the bones are in close association.
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Orbital arches are notorious, the masseter muscles are heavy and bulky. These contribute to the width of the head and reflect the power and strength of the bite to the cover. The dental setting of the upper and lower jaws is scissors. This means that the upper incisors close just ahead the bottom.
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Caenagnathus ('recent jaw') is a genus of caenagnathid oviraptorosaurian dinosaur from the late Cretaceous (Campanian; ~75 million years ago). It is known from partial remains including lower jaws, a tail vertebra, hand bones, and hind limbs, all found in the Dinosaur Park Formation of Alberta, Canada. Caenagnathus weighted about a maximum of .
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Many dsungaripterids have often been seen as durophagous species that cracked shellfish with their convex teeth. Ordosipterus shows a moderate bulge in its teeth, but not the extreme outgrowth that would have been useful for cracking. The broad lower jaws suggest a different way of eating, though Ji does not consider this issue.
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In lancetfishes, the fangs appear on both the upper and lower jaws while in daggertooths the fangs are only seen along the upper jaw. Whether it is the fangs or the distinctly protruding mandible that inspired the common name "daggertooth" remains unclear. Anotopterus spp. have been reported to grow to as long as .
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The specific name refers to the animal's similarity to the North American species Catopsalis joyneri, which Kielan-Jaworowska thought was a possible descendant. The specimen, collected at the Hermiin Tsav I locality, is an almost-complete skull of a juvenile with portions of the cranium damaged. Kielan-Jaworowska also assigned other specimens to the species: a damaged skull missing lower jaws (ZPAL MgM−I/79, an adult), a skull with partial lower jaws (ZPAL MgM−I/80), and a molar with a fragment of jaw (ZPAL MgM−I/159 from Khulsan, the only specimen not from the Hermiin Tsav I and II localities). Three skulls with jaws (A and B were collected in 1975, C in 1999), showing differences in size related to their individual ages.
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The snout is short and the eye sockets are very large. The lower jaw is slender, with a projection called the coronoid process very prominent. The skull bears many small teeth, including a pair of canines in the upper and lower jaws. Each postcanine tooth has lateral grooves on its surface, creating several small cusps.
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Page 538. It may have been closely related to contemporaneous dinosaurs in North America. This genus is known from teeth and possibly partial lower jaws. The name is also in use for a genus of modern moss, but this is not considered to be a problem because the two organisms are in two different kingdoms.
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The halfbeaks' fossil record extends into the Lower Tertiary. The earliest known halfbeak is Brachyrhamphus bolcensis from the Eocene at Monte Bolca, Italy. Apart from differences in the length of the upper and lower jaws, recent and fossil halfbeaks are distinguished by the fusion of the third pair of upper pharyngeal bones into a plate.
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In 1914, Hooley renamed it into Lonchodectes machaerorhynchus. Its holotype, CAMSM B54855, was found near Cambridge, in a layer of the Cambridge Greensand dating from the Cenomanian but containing reworked fossils from the Albian. It consists of the rear end of a symphysis of the lower jaws. Also in 1869, Seeley informally named "Ptenodactylus microdon".
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Although the closest living relatives of Cimolichthys are lancetfish and lizardfish, the living animals would have resembled very large freshwater pikes. Their bodies were covered by large, heavy scutes. Typical of this species are narrow lower jaws with several series of teeth. Remains of undigested fishes or squids have been found in collected specimens.
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Thought to be herbivorous because of the lack of teeth and movement of lower jaws that appeared to be efficient in mastication. Zambiasaurus had a barrel shaped body that was strongly built but very slow. The body was help off the ground but it either had a sprawling stance or a more upright stance.
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The fish rotates its lower and upper jaws to scrape the substrate. Of the two, the lower jaws are more mobile. Loricariid catfishes have evolved several modifications of their digestive tracts that function as accessory respiratory organs or hydrostatic organs. These complex structures would have been independently evolved a number of times within the family.
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The skull consists of only the parietals, and the lower jaws are limited to their upper rear bones, the surangulars and articulars. A fifth specimen is MOR 456.1, a subadult. None of the specimens were of an advanced individual age. According to Andrew McDonald and colleagues, the Achelousaurus finds represented single individuals, not bone beds.
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SEMs of adult lower jaws. (A) Homodont unicuspid snake, Python molurus, (B) homodont gecko, Paroedura picta, (C) homodont tricuspid Monitor lizard, Varanus niloticus, (D) heterodont anole, Anolis allisoni. (D′) Tricuspid teeth of the posterior jaw at the back of the mouth. (D″) Unicuspid teeth of the anterior jaw at the front of the mouth.
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Sereno, P & Z-M Dong (1992). The skull of the basal stegosaurian Huayangosaurus taibaii and a cladistic diagnosis of Stegosauria. Journal of Vertebrate Paleontology 51: 318-343 The upper and lower jaws are equipped with rows of small teeth. Later species have a vertical bone plate covering the outer side of the lower jaw teeth.
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2 was seen as longer than five metres. Dong e.a. indicated that Chungkingosaurus strongly resembled Tuojiangosaurus, found in the same formation, in many anatomical details. Chungkingosaurus was different in its smaller size, deeper snout and front lower jaws (resulting in a relatively high and narrow skull), and non-overlapping teeth with less pronounced denticles.
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Trematosaurs and capitosaurs became independently aquatic and also returned to this type of feeding. Most aquatic stereospondyls have flattened heads. When feeding, they probably opened their mouths by lifting their skulls instead of lowering their lower jaws. The jaw mechanics of the plagiosaurid Gerrothorax is well known, and is one of the most highly adapted.
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Omnivoropterygidae (meaning "omnivorous wings") is a family of primitive avialans known exclusively from the Jiufotang Formation of China. They had short skeletal tails and unusual skulls with teeth in the upper, but not lower, jaws. Their unique dentition has led some scientists to suggest an omnivorous diet for them.Czerkas, S. A. & Ji, Q. (2002).
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Both the tips of the upper and lower jaws of the male B. idiomorpha become fused to the female. Small openings to the mouth and opercular cavities of the male are maintained on both sides. Mature female B. idiomorpha contain around 7500 eggs per ovary, and have some of the largest eggs amongst the deep-sea anglerfish.
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The holotype IVPP 84019 was discovered in the Junggar Basin, in layers of the Wucaiwan Formation dating from the Bathonian-Callovian. It consists of a rather complete skeleton including the skull, lower jaws, vertebral column and pelvis. The rear of the tail, the shoulder girdle and the limbs are lacking. It represents an adult or subadult individual.
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Polymorphodon is named based on a holotype specimen, SMNS 91343. This specimen is a disarticulated collection of bones from a single skeleton. It includes parts of the skull, a partial braincase, palatal fragments, sections of the lower jaws, bones of the hip and hindlimb, tail vertebrae, and potential hand bone fragments. Another specimen, SMNS 91400, consists of skull fragments.
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The wingspan of Ferrodraco was estimated at . The describing authors indicated two autapomorphies (distinguishing traits) that Ferrodraco had. The first tooth pair in both the premaxillae of the snout and in the front lower jaws is smaller than the other front teeth. The fourth to seventh tooth pairs are smaller than the third and eight pair.
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Additionally, a unique combination is present of traits that in themselves are not unique. The front edge of the premaxilla is flattened and triangular. The first tooth pair in the premaxillae is directed vertically and is slightly set-off to above from the jawline. The front parts of the upper and lower jaws are not expanded sideways.
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The anal fin has three spines and 7 to 9 soft rays. The pectoral fins have 15 to 17 soft rays, with all the rays branched except for the uppermost two. The caudal fin is truncate to lunate in shape with 15 soft rays. Both the upper and lower jaws have a pair of forward-facing canines.
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Stangerochampsa is an extinct genus of globidontan alligatoroid, possibly an alligatorine or a stem-caiman, from the Late Cretaceous of Alberta. It is based on RTMP.86.61.1, a skull, partial lower jaws, and partial postcranial skeleton discovered in the late Campanian–early Maastrichtian-age Horseshoe Canyon Formation. Stangerochampsa was described in 1996 by Wu and colleagues.
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The Meckelian Cartilage, also known as "Meckel's Cartilage", is a piece of cartilage from which the mandibles (lower jaws) of vertebrates evolved. Originally it was the lower of two cartilages which supported the first branchial arch in early fish. Then it grew longer and stronger, and acquired muscles capable of closing the developing jaw.The Gill Arches: Meckel's Cartilage, palaeos.
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Saharastega is an extinct genus of basal temnospondyl which lived during the Late Permian period, around 251 to 260 million years ago. Remains of Saharastega, discovered by paleontologist Christian A. Sidor at the Moradi Formation in Niger, were described briefly in 2005 and more comprehensively in 2006. The description is based on a skull lacking the lower jaws.
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Tarpons grow to about long and weigh . They have dorsal and anal soft rays and bluish or greenish backs. Tarpons possess shiny, silvery scales that cover most of their bodies, excluding the head. They have large eyes with adipose eyelids and broad mouths with prominent lower jaws that jut out farther than the rest of the face.
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These skull bones include a maxilla (ALM 1), and several lower jaws (ALM 2, 3, 5, 6, and 7). One of the jaws, ALM 2, connected to a small angled bone tentatively identified as a quadratojugal. The referral of the skull fossils to Arganasuchus is uncertain but likely considering their "rauisuchian" identity and similar size and occurrence.
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The specific name means "very long" in Latin, again in reference to the lower jaws. The holotype is the mandible, specimen MLP-118 (Museo de La Plata). In 1889 Ameghino emended the name to a more grammatically correct Phororhacos but the earlier name has priority. In 1891, it was by him recognized to be a bird.
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The lateral groove and associated foramina are located high on the outer surface of the dentary. The anterodorsal margin of the dentary is curved downward. The symphysis of the lower jaws is heavily built while the leading edge is vertical in side view. The front jaw points are wide in plan view, encountering each other at an obtuse angle.
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Although the phylogenetic position of Brasilotitan is difficult to establish, the new species is neither basal nor a derived member of Titanosauria. Based on lower jaw morphology, it appears to be closely related to Antarctosaurus and Bonitasaura. This discovery enriches the titanosaur diversity of Brazil and provides further new anatomical information on the lower jaws of those herbivorous dinosaurs.
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The dentition of the lungfish is unusual: two incisors, restricted to the upper jaw, are flat, slightly bent, and denticulated on the hind margin. These are followed by dental plates on the upper and lower jaws. Juveniles have different body proportions from mature adults. The head is rounder, the fins are smaller, and the trunk is more slender.
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Adults regularly reach 40 cm in length, but some grow to 64 cm. It has a flattened, tapering head and marbled eye. The brown or black lateral and dorsal scales are tipped white, while the ventral scales are all-white. Long recurved fangs are present on the upper as well as lower jaws, for which they are named.
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Hyotheridium is a possible Eutherian from the Late Cretaceous (?late Santonian–early Campanian) Djadochta Formation of Mongolia. It also could be a Deltatheriid, although the fossil, a poorly preserved skull with the upper and lower jaws connected in a way that makes them hard to separate and to examine, makes it difficult to determine what it is.
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Cranial elements The describing authors indicated a number of distinguishing traits. Some of these are autapomorphies, unique derived characters. The quadrate has a flat facet contacting the quadratojugal. The symphysis of the lower jaws, in which they are fused at the front, is extremely thickened at the top front end, while the top surface is expanded to the rear.
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The front snout bone, the premaxilla, bears a crest with ridges and grooves that curve to the front. The groove on the dentary reaches the highest point of that bone. Both the snout tip and the tip of the lower jaws are slightly expanded. The deltopectoral crest is moderately twisted around the longitudinal axis of the humerus.
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The upper surface of the symphysis or fusion of the lower jaws shows elevated but blunt ridges on its edges. This symphysis has a V-shaped cross-section, thus lacking a lower crest. The underside of the atlas-axis complex of the neck is flat. In the middle neck vertebrae the front articulation processes, the prezygapophyses, lightly diverge.
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The back of the skull bears a long and narrow parietal crest, sticking out at an angle of 15° to the longitudinal skull axis. Not taking into account the crest, the skull is 11.5 times longer than tall. The neck vertebrae are five times longer than high. Moganopterus shows an extreme elongation of the upper and lower jaws.
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The specific descriptor deinosauriscus, "little dinosaur", alludes to the animal's small size for a dinosaur. The holotype, ZPAL MgD-II/29, was discovered in Late Cretaceous river sandstones of the Djadokhta Formation beds, dating from the late Campanian. It consists of an articulated but fragmentary skull and lower jaws comprehending paired maxillae, a partial jugal, palate bones and dentaries.
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It contains six vertebrae, the coracoids, the humeri, a right radius and three spines. The original material has been supplemented after November 1978 by Zhou Shiwu of the Municipal Museum of Chongqing. A second specimen, CV 202, was referred. It represents a skeleton with a partial skull and lower jaws, some vertebrae and limb elements, and four plates.
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The genus name is derived from Tendaguru and a Latinized Greek pteron, "wing". The specific name honors Reck. The genus is based on holotype MB.R.1290, a partial mandible with teeth (the symphyseal region, where the two lower jaws meet and fuse into one element). The top of the back of the symphysis is very concave.
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Comahuesuchidae is a family of notosuchian crocodyliforms. Constructed in 1991, it includes the genera Comahuesuchus and Anatosuchus. Among the characteristics that are unique to this family is an external naris that is inset into the tip of the snout. There is also a diastema, or gap between the teeth, at the tip of the upper and lower jaws.
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Victoriapithecus macinnesi had a dental formula of 2:1:2:3 on both the upper and lower jaws. Its lower molars are bilophodont with low cusps. The canines show sexual dimorphism and the mandible is relatively deep compared to other Old World monkeys. On the forelimbs, the distal end of the humerus shows a narrow articulation and a deep ulnar notch.
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Each lower jaw dentary bears ten teeth. Where the dentaries touch each other, at the front of the lower jaws, they possess a common "chin", equalling a third of the front height. The horizontal groove in the inner side of the dentary, the fossa Meckeliana, largely opens to below. The anterior middle neck vertebrae are pierced by a foramen in the rear side.
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Skeletal advancement in an effort to physically increase the pharyngeal airspace is often an option for craniofacial patients with upper airway obstruction and small lower jaws (mandibles). These syndromes include Treacher Collins syndrome and Pierre Robin sequence. Mandibular advancement surgery is one of the modifications needed to improve the airway, others may include reduction of the tongue, tonsillectomy or modified uvulopalatoplasty.
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Waggoneria is a genus of seymouriamorph from the Early Permian of Texas. It was named by American paleontologist Everett C. Olson in 1951 on the basis of a holotype fossil that included a weathered skull, lower jaws, vertebrae, and part of the pectoral girdle. The type and only species is W. knoxensis. A new family, Waggoneriidae, was also erected for the specimen.
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The skull is crowned by a large rounded crest that continues to behind, descending over the parietals. The crest is very thin, about half a millimetre at the upper part. The jaws are toothless. The profile of the symphysis of the lower jaws closely fits the edge of the upper jaws: when closing the beak, no gap would have remained.
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The genus is based on holotype CAR-0018, an almost complete but crushed 161 millimetres long mandible (fused lower jaws), which differs from that of all known other ctenochasmatids in its short teeth and low tooth count (eleven per side). Also a detached hyoid is present.Dong, Z., and Lü, J. (2005). A New Ctenochasmatid Pterosaur from the Early Cretaceous of Liaoning Province.
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The lips are black and close fitting with the corner of the mouth not visible. The gums should be black, or as dark as possible. Both the upper and lower jaws are strong and broad. According to the FCI Standard Rottweilers should have strong and complete dentition (42 teeth) with scissor bite, the upper incisors closely overlapping the lower incisors.
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Sinoconodon is known only from the skull and lower jaws. It is younger geologically than some Morganucodon, but Sinoconodon has many features which are more primitive than Morganucodon. Particularly significant is the dentition of Sinoconodon, in which the postcanine tooth row consists of five multicuspid trenchant teeth with only the vestiges of cingula. These teeth do not precisely occlude with one another.
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Guidraco is known only from the holotype IVPP V17083, an articulated partial skeleton consisting of a nearly complete skull, lower jaws and a series of four, second to fifth, cervical vertebrae. It was collected at Sihedang near Lingyuan City in the Liaoning Province from the Jiufotang Formation, dating to the Aptian stage of the Early Cretaceous, about 120 million years ago.
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The genus name is derived from Oglala tatanka, "bison" and Greek kephale, "head", in reference to the rounded head form. The specific name honours the family of John Patrick Cooney. The holotype is MOR 1073, a partial skull with an estimated total undamaged length of 32 centimetres, lacking the lower jaws. Also some ribs, osteoderms and a tooth have been recovered.
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The distance of the eyes is less than two-thirds the length of the snout. Also, it has a shorter, broad snout with a single row of irregularly spaced sharp teeth on the upper and lower jaws. No bony scales are on the throat. Their color is olive-brown on the back and upper sides, with a white to yellow belly.
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Counillonia was a medium-sized dicynodont (skull length of ) currently known only from a single skull that's missing the lower jaws. However, it likely resembled other closely related dicynodonts, particularly Dicynodon itself, and so was probably a squat, sprawling quadruped with a short tail and a large head with nearly toothless jaws and a tortoise-like beak, sporting a pair of prominent tusks.
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Such teeth numbered four to six in the praemaxilla and about fourteen to twenty-five in the maxilla; the number in the lower jaws roughly equalled that of the skull. The teeth were placed in tooth-sockets, had vertically wrinkled enamel and lacked a true cutting edge or carina. With some species, the front teeth were notably longer, to grab prey.
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Furthermore, the existing theory that because juvenile needlefish pass through a developmental stage where the lower jaw is longer than the upper jaw (the so-called "halfbeak stage") the theory that halfbeaks are paedomorphic needlefish is untenable. In fact the unequal lengths of the upper and lower jaws of halfbeaks appears to be the basal condition, with needlefish being relatively derived in comparison.
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The skull of Zambiasaurus submersus was reconstructed by using eighteen different juvenile fossil fragments and fragments of an adult Zambiasaurus. The immature skull had the dimensions of long and wide while the adults had a skull long and wide. There are no teeth in both upper and lower jaws making it a herbivorous species. Skull tapers anteriorly, widest across occiput.
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"New reptilian generic names". Copeia 163: 58-59 Owen described Cynosuchus suppostus as similar to Cynochampea in where the incisors and canines are located. The difference is that Cynosuchus suppostus had smaller and more upward location of nostril. The external nostril of Cynosuchus suppostus along with the forends of the upper and lower jaws were close in location with the nostril nearly horizontal.
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In comparison to other therocephalians, Purlovia has a very wide skull due to a widened temporal region. Viewed from above, it looks roughly triangular. The skull is about long, with nearly half its length in the postorbital region behind the eye sockets. It has large canine teeth and smaller buccal, or cheek teeth, along the thick upper and lower jaws.
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Siquisiquesuchus is based on MBLUZ–P–5050, a nearly complete skull and lower jaws. It was found near Lara in rocks of the Early Miocene-age Castillo Formation. Two other partial skulls, partial vertebrae, a thigh bone, partial upper arm, and partial shin bone were recovered from another locality. These bones were described by Christopher Brochu and Ascanio Rincón in 2004.
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The first pair of pharyngeal bars later evolved to form the upper and lower jaws of vertebrates. The second pair evolved to form the hyoid arch. In vertebrates this supports the jaws and the hyoid bone anchors the base of the tongue. The discovery of Metaspriggina makes the origins of gnathostomatans a little more confusing, as it was roughly contemporary with Pikaia.
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The teeth are small and arranged in a dense quincunx pattern; each tooth has a single sharp cusp. There are around 22–24 and 20–22 tooth rows in the upper and lower jaws respectively. The five pairs of gill slits are placed on the underside of the disc. The pelvic fins are distinct from the disc and have rounded outer margins.
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I. Palaeontographical Society, London, 19 pp It was in 1869 renamed by Seeley into a Ptenodactylus sedgwickii, and in 1870 into a Ornithocheirus sedgwickii. In 1874, Owen again renamed it into Coloborhynchus sedgwickii.Owen, R., 1874, Monograph on the fossil Reptilia of the Mesozoic Formations. Palaeontographical Society, London, 14 pp Owen in 1859 also referred a front of the lower jaws, specimen CAMSM B54421.
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As of 2013, the fossil record of extinct koalas consists of 163 specimens across 58 deposits in Riversleigh; 55 specimens are attributed to the Riversleigh rainforest koala.Black, K. (2014) p. 1188. To date, a partial skull has been found along with several lower jaws and isolated teeth. On the basis of these fossils, the dental apparatus of the animal has been completely restored.
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Lower jaws and teeth The lower jaw is long and low. At its rear side, a large armour plate is present. According to Arbour and Evans, this is not a fused osteoderm, but instead an outgrowth of the jaw bones themselves. The adductor fossa, the opening through which the muscles closing the jaw entered its hollow inside, is relatively small and shallow.
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The kunekune kunekune - Māori Dictionary is a small breed of domestic pig from New Zealand. Kunekune are hairy with a rotund build, and may bear wattles hanging from their lower jaws. Their colour ranges from black and white, to ginger, cream, gold-tip, black, brown and tricoloured. They have a docile, friendly nature, and are now often kept as pets.
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It consists of a partial skeleton, including the snout, the front lower jaws, the last back vertebra, six sacral vertebrae, sixteen front tail vertebrae that may or may not have formed a natural series, the complete pelvis, and the hindlimbs (minus the right toes). Many of the bones are damaged and compressed. It is part of the collection of the Royal Ontario Museum.
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Gwawinapterus beardi is known from a single fossil specimen, consisting only of the front half of a skull (upper and lower jaws). The tip of the snout is rounded and deep with a height of about . The tip is about from the front edge of the largest skull opening, or fenestra. Below this opening the upper jaw is about tall.
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SAM 5882, the holotype for Mesosuchus, consists of a partial rostrum, palate, braincase, lower jaws, sections of articulated presacral vertebral column, nine articulated caudal vertebrae, portions of scapula and pelvic girdle, and partial forelimb and hindlimbs. SAM 6046, one of the paratypes of Mesosuchus, consists of an incomplete right maxilla, an articulated series of the last ten presacrals, both sacrals, and first six caudals, partial forelimbs, left and right pelvic girdles, right hind limb, as well as element of left tarsus. SAM 6536, another paratype, consists of a virtually complete skull with lower jaws, articulated cervical vertebrae and ribs, dorsal vertebrae and ribs, complete left scapulocoracoid and partial right scapula, interclavicle, clavicles, distal end of left humerus, and gastralia. 50px This article contains quotations from this source, which is available under the Creative Commons Attribution 4.0 International (CC BY 4.0) license.
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Other specimens were referred: MgD-Ij116, a skull and lower jaws of a juvenile; MgD-Ij 118, fragmentary postcrania and lower jaws of a juvenile; MgD-Ij119, a dentary and three neural arches; MgD-IjI20, two dentaries and loose teeth; MgD-JjI21, a maxilla fragment with four teeth of a juvenile; and MgD-JjI22, teeth. They were then named as a separate genus, Breviceratops, by Sergei Mikhailovich Kurzanov in 1990, the generic name combining the Latin brevis, "short", with a reference to the Ceratopsia.Kurzanov, S., 1990, "A new Late Cretaceous protoceratopsid genus from Mongolia", Palaeontological Journal, 24: 85-91 Kurzanov also referred an additional number of fossils from Khermin Tsav, the type locality of Bagaceratops, to the new genus. The Khermin Tsav specimens closely resemble Bagaceratops, which has led to the proposal that Breviceratops and Bagaceratops are synonymous.
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The front of the lower jaws is fused into a symphysis for a fifth of their lengths. The coracoid does not have a clear process to contact the side of the breastbone. The outer and intermediate rear processes of the breastbone are thin and project to the rear to the same level. The central xiphoid process at the rear of the breastbone is V-shaped.
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Phascolotherium was one of the first mammals described from Mesozoic-aged rocks. It is only known from single lower jaws and some isolated teeth. Buckland showed the fossil jaws of Stonesfield to the exceptional comparative anatomist, Georges Cuvier, who incorrectly identified them as marsupials, based on the similarity of the bones to modern marsupials. Blainville also attributed the fossil to his newly erected genus, Amphitherium.
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The original bone tissue is no longer present but the calcium phosphate mineralisation has preserved the structure of original bone cells, showing individual osteocytes including their inner hollow spaces and the canaliculi. Also the internal blood vessels of the bone have been preserved, in some cases still empty inside. On some bones, including some of the skull and lower jaws, the periosteum is still visible.
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The surfaces of the upper and lower jaws are plate-like and contain several rows of teeth. The lower jaw is deep, possibly associated with the crushing function of the teeth. Olson only tentatively assigned Waggoneria to Seymouriamorpha, noting other similarities with diadectomorphs and procolophonians. Several other fossils found from the Vale Formation share similar features with Waggoneria but differ slightly in size and morphological detail.
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Adults can reach lengths of to and weigh about 2.32 to 3.48 tons. At birth they may be about long. They are robust and large-bodied for beaked whales, having a bluff melon and a long, dolphin-like beak. It is the only species of ziphiid with a full set of functional teeth (17 to 27 pairs in both the upper and lower jaws).
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These pits were filled with specially chosen and arranged bones, particularly those of the lower jaws and ribs of animals. All aspects of the everyday life and work of the Kargaly professionals were saturated in ritual. Gorny, in particular, exhibits various and consistent manifestations of these rituals. Numerous oracle bones were discovered, most likely those of the miners, representative of their difficult and dangerous work.
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Skull of Abdalodon In left lateral view. Photo courtesy of Christian Kammerer. The only existing specimen for Abdalodon is an incomplete, dorsoventrally crushed skull, In which the lower jaws are tightly occluded to the palate. Abdalodon diastematicus is characterized by the presence of diastema between the canines and postcanines of the dentary, and on the maxilla, an even longer diastema between the canines and postcanines.
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The Hemiodontidae are a small family of freshwater characins found in northern South America, south to the Paraná-Paraguay Basin. The larger species are popular food fish. Hemiodontids have a streamlined body shape; many are fast- swimming, and are able to leap out of the water to escape predators. The adults of all species except Micromischodus sugillatus have no teeth on their lower jaws.
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Triaenops goodmani is an extinct bat from Madagascar in the genus Triaenops. It is known from three lower jaws collected in a cave at Anjohibe in 1996, and described as a new species in 2007. The material is at most 10,000 years old. A bat humerus (upper arm bone) from the same site could not be identified as either T. goodmani or the living T. menamena.
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In 2001, it represented the oldest known American stegosaur. It consists of a nearly complete skull and much of the skeleton. It includes the disarticulated elements of the skull, the rear lower jaws, a hyoid, thirteen neck vertebrae, thirteen back vertebrae, three sacrals, forty-four tail vertebrae, neck ribs, dorsal ribs, chevrons, a left shoulderblade, a complete pelvis, ossified tendons and ten neck and back plates.
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Repelinosaurus was a medium-sized dicynodont (largest skull length of ) currently known only from skulls missing lower jaws and the rest of the skeleton. However, it likely resembled other kannemeyeriiform dicynodonts, and so was probably a heavily built, stocky-limbed quadruped with a short tail and a large head with nearly toothless jaws and a tortoise-like beak, sporting a pair of prominent tusks.
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Siamoadapis is an extinct genus of adapiform primate. Remains of its only known species, Siamoadapis maemohensis, were found in Thailand. The fossils were discovered in the lignite layer of a coal mine in Mae Mo district, Lampang Province, northern Thailand, from which it also received its scientific species name. Four lower jaws with teeth were unearthed by a joint team of Thai and French geologists in 2004.
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The fourth dentary tooth is raised in the lower jaw to form an effective canine. The foremost teeth of the lower jaw are much smaller and lower than the fourth tooth. At the tip of the jaw the first dentary tooth is procumbent, or directed forward. The teeth of the upper and lower jaws form an alternate pattern to allow the jaw to close tightly.
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In reproductively mature males, the head becomes elongated and prominent external teeth develop on the upper and lower jaws. Males with teeth tend to have larger gonads than those without. The coloration is a uniform pale white with a pinkish hue caused by subdermal capillaries, especially over anal fin pterygiophores (fin support bones). The operculum is pink due to the presence of the gills underneath.
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The tooth enamel is slightly wrinkled. The third incisor on the upper and lower jaws are small and vestigial. upper jaw in lateral (A) and occlusal view (B), believed to be from an adult male The molars are low-crowned (brachydont), with relatively rounded (bunodont) cusps running lengthwise (selenodont), resulting in a condition known as bunoselenodonty. The upper molars also lack a distinctive cusp (hypocone).
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Babiacetus was named by in an abstract based on the specimen's type (GSI 19647, left and right dentaries with cheek teeth). Gingerich and colleagues found a skull (GSP-UM 3005, much of a skull and lower jaws) while collecting a skeleton of a new species of Protosiren (Protosiren sattaensis) in the Drazinda Formation (, paleocoordinates ). Retrieved April 2013. in the Sulaiman Range of Punjab, Pakistan.
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Hemiramphidae is a family of fishes that are commonly called halfbeaks, spipe fish or spipefish. They are a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The halfbeaks are named for their distinctive jaws, in which the lower jaws are significantly longer than the upper jaws. The similar viviparous halfbeaks (family Zenarchopteridae) have often been included in this family.
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The specific name americanus refers to the fact that the species represents the first unequivocal very basal neoceratopsian found in America. The holotype, OMNH 34557, was found in a layer of the Cloverly Formation, dating from the middle-late Albian. It consists of a skull with lower jaws, of a subadult individual. The rear of the head and the palate are the main lacking parts.
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It consists of a partial skeleton with skull. It contains the lower side of the skull, a left postorbital, the lower jaws, the last sacral vertebra connected to the two front tail vertebrae, a series of seven front or middle tail vertebrae, chevrons, the right shoulder joint with a piece of the humerus, the pelvis, both thighbones and the left foot. It represents a juvenile individual.
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The banded killifish has a row of small sharp teeth lining their upper and lower jaws. It does not have a lateral line along the side but does have 39 to 43 cycloid scales in the lateral series. The average banded killifish ranges from 10 to 13 cm in length and weighs a few grams. The females tend to grow larger than the males.
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It is also the first ostodolepid known from outside North America. Like other ostodolepids, Tambaroter has a pointed snout. Bones in the cheek region are indented upward, leaving a large gap in the bottom of the back of the skull. Tambaroter and other ostodolepids have prominent projections in the back of the lower jaws called retroarticular processes, which are not as well developed in other microsaurs.
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Kevin Padian (2008). The Early Jurassic Pterosaur Dorygnathus Banthensis(Theodori, 1830). Special Papers in Palaeontology No. 80, The Palaeontological Association, London In the lower jaws the first three pairs of teeth are very long, sharp and pointing outwards and forwards. They contrast with a row of eight or more upright-standing much smaller teeth that gradually diminish in size towards the back of the lower jaw.
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The describing authors indicated some distinguishing traits. One of these was an autapomorphy, a unique derived character. The upper surface of the symphysis of the lower jaws shows a well-developed elevation on the midline in a relatively forward position of eighteen centimetres behind the mandible tip, compared to thirty-two centimetres with the related form Alanqa. A second trait is a possible autapomorphy only.
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Handbuch der Paläoherpetologie, Teil 19. Gustav Fischer Verlag, Stuttgart and New York, 82 pp It was found in a layer of the Chalk Formation, dating from the Cenomanian-Turonian. It consists of the front of a snout, the front of a pair of lower jaws, a piece of a scapulocoracoid, the upper parts of a humerus and an ulna, and a part of a wing finger phalanx.
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Deighton, Bell, and Co., Cambridge, xii + 135 pp The specific name means "sabre snout" in Greek. In 1914 Hooley renamed it into Lonchodectes machae[r]orhynchus. Its holotype, CAMSM B54855, was near Cambridge found in a layer of the Cambridge Greensand dating from the Cenomanian but containing reworked fossils from the Albian. It consists of the rear end of a symphysis of the lower jaws.
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The holotype, MIM F1, was excavated from a marine deposit of the Sannine Chalk dating from the late Cenomanian, about ninety-five million years old. The layers were deposited off the coast of the Afro-Arabic plate, in the south of the Tethys Sea. It consists of a relatively complete skeleton with skull and lower jaws. It lacks some vertebrae and some pelvic elements.
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The specific name is a combination of the Latin planus (meaning "flat"), and the ancient Greek gnathos (meaning "jaw"). The holotype, IG V13-011, has been found in a layer of sandstone, belonging to the lower Luohandong Formation, and may be dated back to the Aptian stage of the Early Cretaceous. The holotype consists only of a set of deformed paired lower jaws forming the mandible.
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Martill deposited the fossil in the collection of the Département de Géologie (Paléontologie), Faculté des Sciences Aïn Chock. Two additional fossils were referred to the species: the specimens FSAC-KK 5006 and FSAC-KK 5007. These are snouts also, with a similar provenance, and showing an almost identical build. Specimen BSP 1997 I 67, a symphysis of the lower jaws described in 1999, was provisionally referred.
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Other specimens that are currently referred to M. mccauleyi include PEFO 31219, complete skull, lower jaws and articulated postcranial skeleton, from Petroglyph phytosaur site (also known as PFV 42) collected by UCMP in 1985, and possibly UCMP 27149, a large skull, from Cowboy (UCMP A257), both from the Petrified Forest Member, Arizona. Both specimen were originally referred to A. buceros by Long and Murry (1995).
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Letognathus is a genus of rhizodont tetrapodomorph that lived during the Carboniferous period.Brazeau, M.D. 2005. A new genus of rhizodontid (Sarcopterygii, Tetrapodomorpha) from the Lower Carboniferous Horton Bluff Formation of Nova Scotia, and the evolution of the lower jaws in this group. Canadian Journal of Earth Sciences 42:1481–1499 Its remains come from the Blue Beach Member of the Horton Bluff Formation, near Hantsport, Nova Scotia.
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Described by William Arthur Parks in 1925, Arrhinoceratops is known from a partially crushed, slightly distorted skull which lacked the lower jaws. The remains were collected from the Neill's Ranch site, along the Red Deer River in Alberta by a 1923 expedition from the University of Toronto.Parks, W.A. (1925). "Arrhinoceratops brachyops, a new genus and species of Ceratopsia from the Edmonton Formation of Alberta".
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Gondwanatheria is an extinct group of mammaliaforms that lived in the Southern Hemisphere, including Antarctica, during the Upper Cretaceous through the Miocene (and possibly much earlier, if Allostaffia is a member of this group). Until recently, they were known only from isolated teeth, a few lower jaws, two partial skulls and one complete cranium. Because of this fragmentary knowledge, their placement is not clear.
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Perhaps a row of vertical osteoderms was present on the upper arms. Compared to the later Ankylosauria, Scelidosaurus was lightly armoured, without continuous plating, spikes or pelvic shield. Rough areas on the skull and lower jaws indicate the presence of skin ossifications. Some of the latest specimens found show partly different osteoderms including scutes on which the keel is more like a thorn or spike.
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Its body is elongated and covered with small, scarcely visible scales; the back is an iridescent blue, while the sides are silvery with a pattern of irregular vertical blue bars. These colors fade rapidly during death. The mouth is large, and the teeth of the wahoo are razor sharp. Both the upper and lower jaws have a somewhat sharper appearance than those of king or Spanish mackerel.
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The nasal passage was reduced with heavy muscle attachments for some unknown purpose. Some have speculated that the muscle attachments were for a proboscis, or trunk, much like that of a tapir or elephant. The lower jaws were very deep and helped support massive chewing muscles to help chew coarse fibrous plants. Teeth resembled those of an armadillo, but were fluted on each side by deep grooves.
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As of 2017, Grich has the highest Jaffe Wins Above Replacement Score (JAWS) of any eligible position player not in the Hall of Fame, although his standard WAR is lower than that of Bill Dahlen and fellow second baseman Lou Whitaker. There are more than 10 Hall of Fame second basemen with a lower JAWS. The JAWS statistic is particularly compelling given that it incorporates both career and peak year statistics.
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Remains from this locality are generally diagnosed on the basis of lower or upper jaws. In only one instance, that of Kuehneodon, has it been possible to match the two up. Some of the lower jaws probably represent the same animals as some of the upper, so the diversity of Paulchoffatiids is very possibly exaggerated. As the site is now a flooded, disused coalmine, further excavations are highly unlikely.
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The entirety of the under belly, inner side of the limbs, and lining of the pouch are pure white. Dentition shows two premolar teeth in both the upper and lower jaws, with the first observed as smaller than the second in the upper jaw. The most obvious feature that distinguishes D. blythi from D. cristicauda is the sandy colour and the lack of a crest on the tail.
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The generic name is derived from Greek πίναξ, pinax, "plank", in reference to the small rectangular scutes covering the head. The specific name honours Granger, who accompanied the 1923 expedition as a paleontologist. The holotype, AMNH 6523, was found in a layer of the Djadokhta Formation, dating from the Campanian. It consists of a partially crushed skull, lower jaws, the first two neck vertebrae, and dermal bones collected in 1923.
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The South Asian river dolphin has the long, pointed nose characteristic of all river dolphins. Their teeth are visible in both the upper and lower jaws even when the mouth is closed. The teeth of young animals are almost an inch long, thin and curved; however, as animals age, the teeth undergo considerable changes and in mature adults become square, bony, flat disks. The snout thickens towards its end.
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Both upper and lower jaws have a band of teeth present and the breast is naked ventrally to completely scaled. The species are often dull in coloration, mostly being silver, getting darker dorsally and lighter ventrally. Often, they have green or blue tinges to their bodies, but fade rapidly after death. A few, such as the orange- spotted trevally, have far more brilliant coloration, incorporating bright orange and yellow spotting.
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A 1905 skeletal reconstruction of Stephanospondylus based partly on material from Onchiodon. Stephanospondylus is known only from several vertebrae and fragments of the upper and lower jaws. It was named in 1882 on the basis of two slabs, the fossils in which were thought to represent two individuals. With the erection of a new genus in 1905, the fossils were considered to be part of a single individual.
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Heterodontagama is an extinct genus of iguanian lizard from the Early Eocene of India. It belongs to the extinct family Priscagamidae, which is otherwise only known from the Late Cretaceous of Mongolia. The type species Heterodontagama borsukae was named in 2013 from several isolated upper and lower jaws found in an exposure of the Cambay Shale in an open-pit coal mine in Gujarat. Heterodontagama has a distinctively heterodont dentition.
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Rhineura floridana varies in total length (including tail) from 18–30 cm (7–12 inches). The head has a shovel- like snout that projects forward past the lower jaws, which is used for burrowing. The eyes are highly reduced and not visible externally. The limbs are absent and, as in other Amphisbaenia, the body is covered by scales arranged in rings giving the animal a worm-like appearance.
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Many skull bones are also crushed and distorted, and some such as the maxillae ("mx"), nasal bones ("ns"), and sclerotic rings ("scl") are displaced. Part of the underside of the skull roof (perhaps the frontals, "?fr") can be seen among the bones of the lower jaws, palate (palatine bone, "pl" + pterygoid, "pt"), and braincase (parasphenoid, "ps" + basipterygoids, "bpt"). Twenty-one small teeth are preserved splaying out from the jaws.
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In the skull, adult males have longer lower jaws than females, as well as larger occipital crests. An individual killer whale can often be identified from its dorsal fin and saddle patch. Variations such as nicks, scratches, and tears on the dorsal fin and the pattern of white or grey in the saddle patch are unique. Published directories contain identifying photographs and names for hundreds of North Pacific animals.
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Ymeria is primarily known from a partial holotype skull including the lower jaws and palate, as well as impressions of the shoulder girdle. The holotype comes from the southern slope of Mt. Celsius on Ymer Island in northeast Greenland. Fossils of Devonian tetrapods like Ichthyostega have been known from Ymer Island since 1929. The skull of Ymeria found in 1947 by a team of paleontologists from Sweden and Denmark.
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The genus is based on holotype IVPP V11726, a crushed fossil found in 1998 at the Sihetun-locality. The layer it was discovered in, was argon-dated at an age of 124.6 million years. It was the first Chinese pterosaur fossil preserving the skull. It consists of the front half of a subadult, including a skull, lower jaws, pectoral girdle, sternum, wings, cervical and dorsal vertebrae, partial pelvis and metatarsals.
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There were triangular nutrient foramina between the plates, each containing the tip of an erupting tooth. The narial fossa (depression) in front of the bony nostril was long, relatively shallow, and less developed than that of Giraffatitan. It contained a subnarial fenestra, which was much larger than those of Giraffatitan and Camarasaurus. The dentaries (the bones of the lower jaws that contained the teeth) were robust, though less than in Camarasaurus.
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Mozambique girdled lizards reach 137.5 mm from snout to vent and 281 mm in total length (based on a captive individual). Males are dark brown to black above with bright orange undersides and black throats. Females and juveniles are dark brown above with small cream spots scattered on the neck and back. The bellies and sides are gray with orange and black mottles on the lower jaws and throat.
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The bent snout features twenty pairs of small teeth with an oval cross-section. That the curvature is no preservation artefact, a post mortem distortion, is indicated by the fact that both known snouts show it. Remarkably, all lower jaws found are straight. The wing span was initially estimated at ; however, later studies indicate that the wing span of Prejanopterus was probably not much (if ever) in excess of .
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Microgale macpheei is known from two specimens: a damaged cranium (skull without mandibles, or lower jaws) lacking the back part (the parietal bones and further back) as well as the incisors, canines, and second premolars; and another damaged cranium lacking the same parts as well as the left toothrow. Both show no evidence of ongoing tooth replacement, indicating that the permanent dentition is complete.Goodman et al., 2007, pp.
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The upper and lower jaws are darkly colored, but are separated by thin, white "lips". The chin, throat, and belly are white to pale grey with a limited number of spots. The flanks are separated into three distinct bands of color — the lightest at the bottom, followed by a thin, grey strip in the middle of the flank, and a dark-grey back. The tall concave dorsal fin is similarly colored.
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The Salamandroidea are a suborder of salamanders, referred to as advanced salamanders. The members of the suborder are found worldwide except for Antarctica, sub-Saharan Africa, and Oceania. They differ from suborder Cryptobranchoidea as the angular and prearticular bones in their lower jaws are fused, and all members use internal fertilization. The female is fertilized by means of a spermatophore, a sperm-containing cap placed by the male in her cloaca.
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The type species is Toretocnemus californicus. Its holotype is UCMP 8100, a skeleton lacking the skull. Merriamia zitteli (Merriam 1903) Boulenger 1904, previously Leptocherius zitteli,Merriam, J.C., 1903, "New ichthyosaurs from the Upper Triassic of California", Bulletin of the Department of Geology of the University of California, 3 (12): 249–263 was renamed Toretocnemus zitteli in 1999. Its holotype is UCMP 8099, a skull, lower jaws and front of the torso.
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As the name implies, Eusthenodon has large tusks that protrude from the upper and lower jaws of the skull. Specifically, along the midline of the snout, two large and stout teeth emerge on the premaxilla. From the incomplete material collected upon the discovery of Eusthenodon, the largest tusks are estimated to have been at least 50 millimeters in length. These two teeth are anteroposteriorly flattened and have distinctive, sharp cutting edges.
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Size of Adeopapposaurus compared to a human. The type specimen, PVSJ568, includes a skull and most of a skeleton to just past the hips. The form of the bones at the tips of the upper and lower jaws suggests it had keratinous beaks. The fossils now named Adeopapposaurus were first thought to represent South American examples of Massospondylus; while this is no longer the case, Adeopapposaurus is classified as a massospondylid.
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The number of teeth in the lower jaws cannot be determined. The flexible tail did not have the stiffening rod-like vertebral extensions present in other basal pterosaurs. The wingspan has been estimated at about 120 cm. Austriadactylus was in 2002 assigned by the describers to a general Pterosauria incertae sedis, but some later analyses showed it to have been related to Campylognathoides and Eudimorphodon in the Campylognathoididae.
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The supratemporal fenestrae, two holes on the skull table, are relatively small. Top view of a cast of the skull of Sebecus icaeorhinus (AMNH 3160) Laterally compressed, or ziphodont teeth, are characteristic of Sebecus and other sebecosuchians. Although the teeth vary in size, they are homodont, having a similar shape throughout the jaw. At the tips of the upper and lower jaws, the teeth are rounder in cross-section.
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"Odontorhynchus" aculeatus was based on a skull with lower jaws that is now lost. This set of jaws supposedly differed in having two teeth united at the tip of the lower jaw, and none at the tip of the upper jaw. The skull was , making it a small form. Stolley, who described the specimen in 1936, argued that R. longicaudus also should be reclassified in the genus "Odontorhynchus".
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The tail vertebrae possessed chevron bones. The dorsal vertebrae of plesiosaurs are easily recognisable by two large foramina subcentralia, paired vascular openings at the underside. The skull of plesiosaurs showed the "euryapsid" condition, lacking the lower temporal fenestrae, the openings at the lower rear sides. The upper temporal fenestrae formed large openings at the sides of the rear skull roof, the attachment for muscles closing the lower jaws.
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Additionally, new lower jaw fragments with larger teeth led to the description of O. grandis, whose holotype (designated MNHN.F PM37) bears a canine tooth and full set of cheek teeth. As of 2014, the skull of Ocepeia is the best-known mammal skull from the Paleocene of Africa (other species are only known from teeth or lower jaws), as well as the oldest known skull of any afrotherian.
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Reconstructed skull of O. daouiensis. Scale bar: Ocepeia shows a mixture of primitive and highly derived traits, including features shared with primitive eutherian mammals as well as features similar to those seen in primitive ungulates ("condylarths") and early paenungulates. The skull of O. daouiensis was about in length and wide, estimated from reconstructions. O. grandis is known only from lower jaws with associated cheek teeth and isolated upper teeth.
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The arrangement of soft tissue and any additional articulations connecting these elements is collectively known as the jaw suspension. There are several archetypal jaw suspensions: amphistyly, orbitostyly, hyostyly, and euhyostyly. In amphistyly, the palatoquadrate has a postorbital articulation with the chondrocranium from which ligaments primarily suspend it anteriorly. The hyoid articulates with the mandibular arch posteriorly, but it appears to provide little support to the upper and lower jaws.
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The correct spelling is Pareidae, not Pareatidae. Many pareids are snail-eating snakes that have asymmetrical lower jaws, allowing them to pry the soft bodies of snails from their spiral shells. One species, Pareas iwasakii, has an average of 17.5 teeth in its left mandible and 25 teeth in its right mandible. Other species lacking asymmetrical jaws, such as Aplopeltura boa and Asthenodipsas malaccanus, feed instead on slugs or lizards.
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The nostrils are preceded by triangular flaps of skin that almost reach the long, angular mouth. The mouth contains prominent papillae on both the roof and the floor, and lacks furrows at the corners. The upper and lower jaws contain on average 65 and 60 tooth rows respectively; each tooth is relatively large, with a narrow central cusp flanked by 1–2 smaller cusplets. There are five pairs of gill slits.
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The fisher and the genus Martes were determined to have descended from a common ancestor, but the fisher was distinct enough to put it in its own genus. It was decided to create the genus Pekania and reclassify the fisher as Pekania pennanti. Members of the genus Pekania are distinguished by their four premolar teeth on the upper and lower jaws. Its close relative Mustela has just three.
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Several physical characteristics distinguish this species from others that live in the region. The lack of pigmentation causes this fish to look pink in color; its blood and internal organs are visible through the scales. Several rows of teeth are accommodated by a big mouth and thick lips. Another factor that helps accommodate the quantity of teeth is the fact that the lower jaws protrude further than the upper jaws.
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Gobiraptor lived in a mesic habitat, one that was half-dry. As its foot was not arctometatarsal and the animal thus was not a specialised running form, the describing authors considered it unlikely that Gobiraptor was a carnivore. Each dentarium had a grinding plate at the top with small holes on the surface. The thick front lower jaws were specialized for crushing food such as bivalves (durophagy) and seeds (granivory).
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Morphological studies on the lower jaws of juveniles of D. terrelli reveal they were proportionally as robust as those of adults, indicating they already could produce high bite forces and likely were able to shear into resistant prey tissue similar to adults, albeit on a smaller scale. This pattern is in direct contrast to the condition common in tetrapods in which the jaws of juveniles are more gracile than in adults.
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Life reconstruction The holotype, MPUM 6009, was found in a layer of the Calcari di Zorzino Formation dating from the early Norian (upper Alaunian). It consists of a partial skeleton including the skull, compressed on a single plate. It is largely articulated and includes the lower jaws, most of the wings, much of the vertebral column except the tail, and hindlimb elements. Some bones have only been preserved as impressions.
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The holotype consists of numerous semi-articulated remains, including an incomplete skull roof, snout, palate, cheeks, lower jaws and associated dermal bones, a left shoulder girdle, and assorted scales. Reconstructions suggest a skull length of 30 cm (12 in) and lower jaw length of about 48 cm (19 in). The endoskeleton shows a large or complete lack of ossification. The orbits (eye-sockets) are somewhat triangular rather than oval-shaped.
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The upper jaws have in total 22 or 24 recurved conical teeth; with the lower jaws they make a short and very wide mouth. The animal is not preserved with a tail. Whether it had one is debatable; usually it is assumed a short tail was present. The wingspan has been estimated at 50 cm (20 in); David Unwin in 2000 gave a higher estimate of 75 cm (30 in).
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The holotype, 41HIII0419, was uncovered in a layer of the Yixian Formation, dating from the Aptian, about 125 million years old. It consists of an almost complete skull with lower jaws and the second to fourth neck vertebrae. The fossil is compressed on a slab and counterslab, the splitting of the two plates having damaged some bones. The specimen is part of the collection of the Geological Museum of Henan.
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Life reconstruction as a marine reptile, a controversial ecological hypothesis Odontochelys differed grossly from modern turtles. Modern turtles have a horny beak without teeth in their mouth. In contrast, Odontochelys fossils were found to have had teeth embedded in their upper and lower jaws. One of the most striking features of turtles, both modern and prehistoric alike, are their dorsal shells, forming an armored carapace over the body of the animal.
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On the thumb claw the raised attachment point for the tendon of the extensor muscle is bordered by deep grooves for ligaments. The large skull opening in the snout, the fenestra antorbitalis, is positioned in a depression which reaches the side of the nasal bone. There are at least five pairs of conical teeth in the front of the lower jaws. These teeth are hollowed-out at the inside.
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The holotype specimen, RTMP 2002.57.5, has been found in a layer of the uppermost Horseshoe Canyon Formation, dated to the early Maastrichtian, about 68.8 million years ago. It consists of a partial skeleton with skull, lacking the lower jaws. It contains a partial skull including parts of the frill sides, large horns above the eyes, and a small horn above the nose, similar to the closely related Triceratops.
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The diet of the silvertip shark consists primarily of bony fishes, such as grouper, mackerel, tuna, escolars, lanternfish, flyingfish, wrasses, and soles. Eagle rays, smaller sharks, and octopus are occasionally taken. Larger sharks tend to be more sluggish and take more benthic prey. The differently shaped dentition in their upper and lower jaws allows them to tackle large prey, gripping and sawing off chunks of flesh with violent twists and turns.
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If the infant is not closing down properly, the lower jaws become more noticeably deficient (micrognathia or retrognathia). The front teeth may not touch when the child closes down because the back teeth have overerrupted or because of incomplete formation of the maxilla. This condition is called an anterior open bite and has facial/skeletal implications. The saliva may be thick, or the infant may have a dry mouth.
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Myrmecodaptria (meaning "ant eater" in Greek) is an extinct genus of scleroglossan lizard from the Late Cretaceous Djadokhta Formation in Ukhaa Tolgod, Mongolia. The type and only species, Myrmecodaptria microphagosa (microphagosa meaning "eating little" in Greek), was named in 2000 by paleontologists Gao Keqin and Mark Norell. Myrmecodaptria is known from a single holotype skull and lower jaws. It is distinguished from all other lizards by its extremely elongated skull.
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The golden skiffia is a small fish, reaching a maximum standard length (SL) of around , with a wedge shaped head and upturned lips. It has of a row 30–35 deeply cleft outer teeth in both the upper and lower jaws. Inner teeth can be cleft or conical, and are scattered irregularly. The species shows sexual dimorphism with males having larger fins, and a greater body and head depth.
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Life restoration of Allognathosuchus gracilis Allognathosuchus was a medium-sized predator up to 1.5 m in length. This alligatorine is known for its stout jaws and bulbous teeth, found near the rear of the tooth row in upper and lower jaws. These adaptations have historically been interpreted as having been for crushing mollusks. Isolated bulbous teeth are often assigned to this genus, although such teeth are known from other crocodyliform lineages.
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It allows the maxilla to pivot in the plane of the photograph, and while it does not increase gape, it does facilitate the complex action by which the snake draws prey into its mouth. Green A: the joint between the frontal bone and nasal bone. It allows the nose to upturn slightly, increasing gape and assisting in swallowing. Green B: allows the lower jaws to bow outwards, further increasing the gape.
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It consists of a partial skeleton with lower jaws. It contains the front and the rear of the symphysis of the lower jaws, a right articular, a rib piece, the distal ends of a left radius and ulna, the proximal and distal end of a left third metacarpal and a piece of a phalanx, probably the first of the left third finger. The fossil is part of the collection of the Staatliches Museum für Naturkunde Stuttgart. It is the most complete pterosaur specimen from the Cretaceous of Germany. In their study of 2010, Fletcher & Salisbury argued for O. wiedenrothi to be an ornithocheirid closely related to the then unnamed Aussiedraco and another pterosaur specimen from the Cretaceous of Australia.Fletcher, T.L. & Salisbury, S.W., 2010. "New pterosaur fossils from the Early Cretaceous (Albian) of Queensland, Australia", Journal of Vertebrate Paleontology, 30(6): 1747-1759. DOI:10.1080/02724634.2010.521929 In 2013, Ford reported it to be a species of Lonchodectes.
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Jiangjun, 將 軍, is "general" in Chinese and the town's name, the "temple of the general", has been explained by the burial of one. The specific name refers to the provenance from the Junggar. The holotype, IVPP V 14724, was found in a layer of the Shishugou Formation, dating from the Oxfordian. It includes the lower jaws, some rear skull bones, eleven neck vertebrae, ribs, a scapula, a coracoid, and two neck plates.
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The most diagnostic features of Lonchodectidae pertain to the teeth and jaws. The teeth on both the upper and lower jaws are generally small, do not vary in size through the length of the jaw, and are placed on raised alveolar margins. The upper palate has a prominent ridge. One genus, Lonchodraco, has prominent crests at the tips of both the skull and mandible, while another, Ikrandraco, only has a crest on the mandible.
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The fishes of the genus Filimanus have a body which is oblong to moderately deep and compressed. They have a well developed adipose eyelid and the diameter of the eye is longer than the length of the snout. They have a well developed lip on their lower jaws and the teeth on the dentary bone are restricted to its dorsal surface. There are narrow bands of villiform teeth on their jaws, palatine bone and ectopterygoids.
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These muscles would be attached on bony ridges present on the upper and lower jaws. The authors interpreted the action of the jaws as limited to simple up–and–down motions, finding forward–backward motion unlikely based on skull articulation. The vertical motion would cut food into short lengths, and the pieces would be retained by the cheeks. To manipulated the food in the cheeks, the authors inferred the presence of a well-developed tongue.
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Kembawacela broadly resembled other cistecephalids in size and shape. It was a small dicynodont (skull length roughly long along the base) and had a highly specialised body plan for digging. Kembawacela is known from skulls, lower jaws and various pieces of postcrania, including parts of the pelvis, femur, ulna and various vertebrae. Its skull is typical for cistecephalids, with a broad head and large temporal fenestra with a very short, tapered snout.
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In 1995 the Italian paleontologist Fabio Marco Dalla Vecchia named a new species of the genus Eudimorphodon: E. rosenfeldi. The specific name honours the finder Corrado Rosenfeld.Dalla Vecchia F.M., 1995, "A new pterosaur (Reptilia, Pterosauria) from the Norian (Late Triassic) of Friuli (Northeastern Italy), Preliminary note". Gortania, 16 (1994): 59-66 The holotype was MFSN 1797, a partial fossil skeleton with parts of the skull and lower jaws, but lacking the tail, found near Udine.
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Small insect-eating bats can have as many as 38 teeth, while vampire bats have only 20. Bats that feed on hard- shelled insects have fewer but larger teeth with longer canines and more robust lower jaws than species that prey on softer bodied insects. In nectar- feeding bats, the canines are long while the cheek-teeth are reduced. In fruit-eating bats, the cusps of the cheek teeth are adapted for crushing.
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The crest has a base length of and a height of . The symphysis of the lower jaws, their front fused area, probably extended to below in a second crest. There is an estimated total of twelve teeth in the upper jaw and thirteen teeth in the lower jaw for a total of fifty in the head as a whole. The teeth are formed as conical spikes with an oval cross-section, transversely flattened.
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Eolydekkerina is known from two specimens: a skull lacking the lower jaws and a poorly lower jaw, not associated with the skull. At in length, the skull of Eolydekkerina is larger than that of any Lydekkerina specimen. The snout is proportionally much longer, and the eye sockets are placed farther apart than they are in Lydekkerina. The proportions of the skull in Eolydekkerina are similar to those of the Australian lydekkerinid genus Chomatobatrachus.
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They have a large, tapering operculum flap, a large mouth, and a flat, paddle-shaped rostrum that measures approximately one-third of their body length. During the initial stages of development from embryo to hatchling, American paddlefish have no rostrum. It begins to form shortly after hatching. The rostrum is an extension of the cranium, not of the upper and lower jaws or olfactory system as with the long snouts of other fish.
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Known material of Echinodon and Tianyulong, related heterodontosaurids, comes from similar-sized individuals, but it is not known how old they were upon death. Fruitadens was similar to Heterodontosaurus in anatomy, with relatively short arms and long distal sections of the legs (feet and shins). The lower jaws had an enlarged canine-like tooth, with a corresponding gap in the upper jaw. Unlike Echinodon, there wasn't an enlarged tooth in the upper jaw.
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The specific name nomadis is the genitive of the Latin nomas, "nomad" and refers to the Nomadic Expeditions travel agency that has organised many palaeontological expeditions to Mongolia. The holotype, MPC D-100/1388, was found in a layer of the Barun Goyot Formation, dating from the mid to late Campanian, about seventy-five million years old. It consists of a skull lacking the snout tip. No elements of the lower jaws were discovered.
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The finetooth shark was originally described as Carcharias (Aprionodon) isodon by French zoologist Achille Valenciennes, in Müller and Henle's 1839 Systematische Beschreibung der Plagiostomen. The type specimen is a 65-cm (26-in) juvenile male, possibly caught off New York. This species was later moved to the genus Carcharhinus. The specific epithet isodon means "equal teeth" in Greek, and refers to the similar number of teeth in the upper and lower jaws.
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Panthera youngi is a fossil cat species that was described in 1934; fossil remains of this cat were excavated in a Sinanthropus formation in Choukoutien, northeastern China. Upper and lower jaws excavated in Japan's Yamaguchi Prefecture were also attributed to this species. It is estimated to have lived about 350,000 years ago in the Pleistocene epoch. It was suggested that it was conspecific with Panthera atrox and P. spelaea due to their extensive similarities.
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The milk shark has a slender build with a long, pointed snout, large, round eyes with nictitating membranes (protective third eyelids), and no spiracles. On each side of the head behind the corner of the jaw, there are usually seven to 15 enlarged pores. The nostrils are small, as are the adjacent triangular skin flaps. There are long furrows at the corners of the mouth on both the upper and lower jaws.
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The gill rakers, dark and bristle-like, are used to catch plankton as water filters through the mouth and over the gills. The teeth are numerous and very small, and often number 100 per row. The teeth have a single conical cusp, are curved backwards, and are the same on both the upper and lower jaws. This species has the smallest weight-for-weight brain size of any shark, reflecting its relatively passive lifestyle.
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It was probably hollowed out by an outgrowth of an air sac in the nasal bone. Such a level of pneumatisation of the jugal is not known from other megalosaurids and might represent a separate autapomorphy. Cast of the lower jaw The lower jaw is rather robust. It is also straight in top view, without much expansion at the jaw tip, suggesting the lower jaws as a pair, the mandibula, were narrow.
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The holotype, MC 11078, was in 1983 uncovered at the "Cantera de la Pala Mécanica"-site in the Lago Pellegrini quarries exploited by Abel since 1975. This single known fossil of Abelisaurus consists of a skull, lacking the lower jaws, that is incomplete, especially on the right side. Most of the connections between the snout and the back of the skull are absent. It is also missing most of the palate (roof of the mouth).
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In 1952, Swedish paleontologist Erik Jarvik first described the first species, Eusthenodon wangsjoi of the genus Eusthenodon. The specimen was retrieved in 1936 from the richly fossiliferous sediments of the Upper Devonian sequences of East Greenland, a region that gained tremendous attraction by vertebrate paleontologists after the discovery of Ichthyostega, the earliest known tetrapod. The given name of the genus, Eusthenodon, refers to the distinctly large tusks present in the upper and lower jaws.
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Similarly, the oldest apeomyine, Zophoapeomys, is smaller and has lower-crowned cheekteeth. The known material of Apeomyoides consists of a number of fragmentary mandibles (lower jaws) and isolated cheekteeth. The length of the first and second lower molars (m1 and m2) ranges from 1.74 to 2.58 mm, the width from 2.08 to 2.33 mm. The fourth upper premolar (P4) has not been recorded, but there is a specimen of its deciduous precursor (DP4).
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116-123 The holotype specimen, GCC V20501, had been dug up in a layer of the Lower Shaximiao Formation. It consists of a partial skeleton with skull. Elements of most parts of the body have been preserved, the skull, vertebral column, shoulder girdle, frontlimbs and hindlimbs but all are very limited and/or damaged. The lower jaws, pelvis and the end of the tail had probably been entirely destroyed by the machine.
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It consists of a partial and disarticulated skeleton with skull. It contains both frontal bones, a left jugal, the lower jaws, loose teeth, vertebrae of the neck, back and tail, the shoulder girdle, both humeri, a first wing phalanx, the pelvis, a shinbone and a calf bone. The fused frontals had in 2003 been incorrectly identified as a breast bone by Wellnhofer. The bones have been partly preserved as impressions only and many are fragmented.
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Livezey, B.C. & Zusi, R.L. (2007): Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion. Zoological Journal of the Linnean Society no 149(1), pp 1-95 Étienne Geoffroy Saint-Hilaire stated in 1821 that he had found a considerable number of tooth buds in the upper and lower jaws of the Palaeornis torquatus (rose-ringed parakeet). Émile Blanchard felt justified in recognizing flakes of dentine.
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The teeth rows stretch from the very front of the head until the back edge of the fenestra nasoantorbitalis. They are associated with oblique cellular structures visible in the bone of the upper and lower jaws, the nature of which has not been determined. Hollow structures, reinforced by struts, can also be seen in the parietal crest and the vertebrae. The fourth cervical is 7.25 times as long as it is tall.
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Both the left foot and testicle were missing. Hitler's dental remains consisted of nine upper teeth with dental work connected by a gold bridge and part of a lower jawbone with 15 teeth (10 of them artificial); the latter was found loose in the oral cavity. The tip of the tongue was "firmly locked between the teeth of the upper and lower jaws." The alveolar processes of the mandible were broken with "ragged edges".
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They, too, have only been found in Pakistan and India, and sediments suggest that they lived in turbid waters in coastal areas. Though they were probably able to live on land, they apparently used their tails to swim. Dozens of fossils have been described, but most are only skulls and lower jaws with few dental and postcranial remains. Remingtonocetids probably varied in size with the smallest species matching Pakicetus and the largest Ambulocetus.
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The snout has a triangular cross-section but its top edge is more rounded than with other azhdarchids. The symphysis of the lower jaws has a U-shaped cross-section in front but a V-shaped one at the rear. The fourth neck vertebra has an Elongation Ratio, horizontal length divided by transverse width, that more approaches the ER of the third neck vertebra of other azhdarchids in being shorter than usual.
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The lower jaws were elongated and met at their tips in a shared epidentary bone, the core of the toothless lower beak. In the dentary bone, the tooth battery curved to the outside to meet the battery of the upper jaw. At the rear of the lower jaw, the articular bone was exceptionally wide, matching the general width of the jaw joint. T. horridus can be distinguished from T. prorsus by having a shallower snout.
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This species can be separated from P. pollachius by looking at the relative lengths of the upper and lower jaws. P. pollachius has a longer underslung lower jaw while P. virens has approximately equal upper and lower jaw lengths. This gives a very different profile to the head. In general, P. pollachius is a brown or golden colour with a dark back while P. virens is bright silver with a very dark green back.
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Cannibalism sometimes takes place, especially when resources are short or time is limited. Tiger salamander tadpoles in ephemeral pools sometimes resort to eating each other, and are seemingly able to target unrelated individuals. Adult blackbelly salamanders (Desmognathus quadramaculatus) prey on adults and young of other species of salamanders, while their larvae sometimes cannibalise smaller larvae. The head of a tiger salamander Most species of salamander have small teeth in both their upper and lower jaws.
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Liliensternus restored with a speculative crest. Liliensternus was approximately long, and may have weighed about . Other estimates suggest that Liliensternus was at best long and weighed at most. The remains of two specimens of Liliensternus together form a syntype series with inventory number MB.R.2175, and consist of the partial and fragmentary skeletons of at least two individuals, containing elements of the skull, the lower jaws, the vertebrae and the appendicular skeleton.
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Restored E. rugosidens skeleton without back armour The skull of Edmontonia, up to half a metre long, is somewhat elongated with a protruding truncated snout. The snout carried a horny upper beak and the front snout bones, the premaxillae, were toothless. The cutting edge of the upper beak continued into the maxillary tooth rows, each containing fourteen to seventeen small teeth. In each dentary of the lower jaws, eighteen to twenty- one teeth were present.
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Sternberg correctly recognized them as part of a meat-eating dinosaur but thought they belonged to an ornithomimid. In 1936, its lower jaws, specimen CMN 8776, were found by Raymond Sternberg near Steveville and in 1940 he gave them the name Caenagnathus collinsi. The generic name means 'recent jaw' from Greek kainos, "new", and gnathos, "jaw"; the specific name honours William Henry Collins. The toothless jaws were first thought to be those of a bird.
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Burnetia is an extinct genus of biarmosuchian therapsids in the family Burnetiidae, from the Late Permian of South Africa. Burnetia is known so far from a single holotype skull lacking the lower jaws described by South African paleontologist Robert Broom in 1923. Due to erosion and dorsoventral crushing, features of the skull are hard to interpret. Stutural lines are further distorted by the unusual shape of the skull roof, including many bosses and protuberances.
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Coloration is confined to the dorsal and lateral sides of the body; the ventral surface is usually translucent. Many individuals have a light, cream- or yellow- colored stripe on the top of the tail. The head is roughly shovel-shaped, broad but relatively short, and widest at the point where the upper and lower jaws meet. Three prominent external gills—often deep red in color—extend from each side of the head.
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Fish head parts, 1889, Fauna of British India, Sir Francis Day Skull of a swordfish The skull of fishes is formed from a series of only loosely connected bones. Lampreys and sharks only possess a cartilaginous endocranium, with both the upper and lower jaws being separate elements. Bony fishes have additional dermal bone, forming a more or less coherent skull roof in lungfish and holost fish. The lower jaw defines a chin.
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Interceptive orthodontic treatment can be initiated at this stage of development to help with crowding or to help relate the upper and lower jaws. Consistent with a high palate is a narrow arch shape of the upper teeth as they line up in the mouth. This may cause the upper front teeth to flare out and become more prone to fracture if accidentally hit. Interceptive orthodontics has an important role in this situation.
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The type specimen was originally described as Macromerium scoticum and lacked a complete skull. With subsequent discoveries, Crassigyrinus is now known from three skulls, one of which is in articulation with a fairly complete skeleton, and two incomplete lower jaws. Crassigyrinus grew up to 2 meters in length, coupled with tiny limbs and unusually large jaws. Crassigyrinus is taxonomically enigmatic, having confused paleontologists for decades with its apparent fish-like and tetrapod features.
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Upper teeth Lower teeth Slim and streamlined, the silky shark has a fairly long, rounded snout with barely developed flaps of skin in front of the nostrils. The circular, medium-sized eyes are equipped with nictitating membranes (protective third eyelids). Short, shallow furrows are present at the corners of the mouth. Fourteen to 16 and 13–17 tooth rows are found on either side of the upper and lower jaws, respectively (typically 15 for both).
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It consists of the complete skull with lower jaws, the cervical vertebrae, some dorsal vertebrae and some ribs. Part of the bony armour scutes or osteoderms were preserved. Later two more large specimens were found, again containing skulls but also providing some information about the shoulder girdle and front limbs: ROM 1215Sternberg, C.M., 1921, "A supplementary study of Panoplosaurus mirus", Transactions of the Royal Society of Canada, Third Series 4: 93-102 and RTMP 83.25.2.
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The generic name is derived from the Batyr, the Kazakh hero warriors. The specific name honours Anatoly Konstantinovich Rozhdestvensky. The holotype, AEHM 4/1, was found near Akkurgan in a layer of the Bostobinskaya Formation dating from the Santonian-Campanian, about eighty-four millions year old. It consists of a partial skeleton, including a partial skull, the lower jaws, sixty individual teeth, the sterna, the right humerus, the left radius, metacarpals and phalanges.
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The skull of the holotype is 390-400 millimeters long (15.4-15.7 inches) and extremely elongated with a slightly concave top. The skull and lower jaws held 76 long, curved needle-like teeth, eighteen in the upper, nineteen in the lower jaw, confined to the beak ends, the anterior third, of the jaws. The second specimen had seventy-eight teeth. The neck vertebrae of the second specimen are very elongated, five times longer than wide.
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The lower jaws are represented by their rear halves, and were heavily built. Of the postcranial skeleton, bones from all areas of the body are represented, except the hind foot. Six fused vertebrae supported the hip, as in Silvisaurus. The ilia, the largest bones of the hip, appear to have been flared out unusually, at 55° compared to the ~30° or ~40° degrees of other nodosaurids, but this could be a preservational accident.
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In May 2018, the first Canadian complete face transplant was performed under the leadership of plastic surgeon Daniel Borsuk at the Hopital Maisonneuve Rosemont, in Montreal, Quebec. The transplant took over 30 hours and replaced the upper and lower jaws, nose, lips and teeth on Maurice Desjardins, a 64-year-old man that shot himself in a hunting accident. At that time, Mr. Desjardins was the oldest person to benefit from a face transplant.
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The predentary, the bone core of the lower beak placed on the fronts of both lower jaws, has a deep and hooked "chin". Between the predentary and the tooth row a gap is present equal to about four tooth positions. From the rear part of a bone shelf at the outside of the tooth row a vertical plate extends upwards obscuring that row in side view. The plate continues to the rear into a high coronoid process.
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Shartegosuchids can also be diagnosed by the position of the teeth in their lower jaws, which are never found behind the mandibular fenestrae (holes found near the back of the jaw). The edges of the teeth are denticulated, or ridged. The shape and position of several bones of the skull, including the frontal, nasal, lacrimal, and quadrate, are also distinctive. Unlike most other archosaurs, shartegosuchids lack an antorbital fenestra, an opening in the skull in front of the eyes.
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Halichoeres maculipinna is generally less than long. The fish is slightly elongated with a nearly symmetrical upper and lower body. It has a pointed snout and rows of small teeth in its upper and lower jaws with two sets of canines in each (at the front and corners of its mouth). Its pectoral fin has fourteen rays, its dorsal fin has eleven rays and nine spines, and its anal fin has eleven rays and three spines.
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The mandibles (lower jaws) are straight and slender, formed by the tooth-bearing dentary bones at the front and the splenial and angular bones at the back. The front tip of the mandibles curves very slightly downwards and inwards. The teeth of Jesairosaurus are pointed and very slightly curved, although they are also conical (particularly so in the maxilla) and only slightly flattened from the side. In addition, the teeth are subthecodont (also known as pleurothecodont).
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Urtinotherium pertains to the Hyracodontidae subfamily Indricotheriinae. These in turn are part of the superfamily Rhinocerotoidea and therefore represent close relatives of modern rhinoceroses. The hyracodontids are distinguished by the formation of large sharp incisors in their upper and lower jaws, while rhinoceroses only have a two on the lower jaw. Urtinotherium was thought of by Leonard Radinsky to be a transitional form between earlier indricotheres, like Juxia, and later forms, such as Paraceratherium and Indricotherium (now Paraceratherium transouralicum).
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Tooth of cf. R. isosceles with close up of denticles The holotype specimen of Richardoestesia gilmorei (NMC 343) consists of the pair of lower jaws found in the upper Judith River Group, dating from the Campanian age, about 75 million years ago. The jaws are slender and rather long, 193 millimeter, but the teeth are small and very finely serrated with five to six denticles per millimeter. The serration density is a distinctive trait of the species.
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Life restoration of Ludodactylus Ludodactylus is based on holotype SMNK PAL 3828, a skull missing part of the head crest, that was removed from the plate before the fossil was illegally sold. Unlike other ornithocheirids (the group of which Ludodactylus was assigned to), it had no premaxillary crest on the snout, but did have a crest at the back of the skull. Frey et al. interpreted the deep mandible as a crest on the lower jaws.
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With the elongated preorbital (in front of the eyes) region of the skull, longer portions of stems could be stripped in a single action. Also, the palinal (backwards) motion of the lower jaws could have contributed two significant roles to feeding behavior: (1) an increased gape, and (2) allowed fine adjustments of the relative positions of the tooth rows, creating a smooth stripping action. Young et al. (2012) used biomechanical modelling to examine the performance of the diplodocine skull.
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The generic name combines the Dawn deity of the Iroquois with a Latin draco, "dragon". The specific name refers to the Kanza tribe of Kansas. 'Dawndraco' is based on the holotype specimen UALVP 24238, a partial skeleton including an almost complete skull and lower jaws. It was recovered in 1974 by Richard C. Fox and Allen Lindoe from rocks of the lower part of the Smoky Hill Chalk Member of the Niobrara Formation in Utica, Kansas.
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The inside of the lower jaws also bore a complex series of ridges and toothlike processes, as well as a pair of horizontal, shelf-like structures. Furthermore, the jaws were unusual in being hollow and air filled, apparently being connected to the air sac system. Caenagnathids also tended to be more lightly built than the oviraptorids. They had slender arms and long, gracile legs, although they lacked the extreme cursorial specializations seen in avimimids and Caudipteryx.
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This specimen, found in Hell Creek Formation rocks, came from northeast of the Black Hills of South Dakota and originally had extensive skin impressions. It was missing most of the pelvis and part of the torso due to a stream cutting through it. The bill had impressions of a horny sheath with a tooth-like series of interlocking points on the upper and lower jaws. When describing this specimen AMNH 5730, Cope assigned it to the species Diclonius mirabilis.
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Triaenops goodmani is known from three mandibles (lower jaws): one with the fourth premolar (p4) and first and second molars (m1–2) and two with the second and third molars (m2–3). The jaw is relatively robust. The p4 resembles a canine, having a single cusp that is about as high as the highest cusp on m1 and lacking accessory shelves or cusps. The molars are narrow-crowned and longer than in T. menamena, P. auritus, and P. furculus.
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Kazaklambia is known from a nearly complete skeleton of a juvenile missing only the snout, the front of the lower jaws, some dorsal vertebrae and end of the tail, holotype PIN 2230, found by G.A. Belenkiy in 1961.G.A. Belen’kiy, “Geological structure of the Tashkent area Chule,” Tashkent Gos. Univ., New Series, No. 181, pp. 1-181, 1961 Although some studies considered it to be possibly synonymous with Jaxartosaurus aralensis, others found the species to be valid.
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It is uncertain how many teeth Elasmosaurus had, due to the fragmentary state of the fossils. It probably had six teeth in each premaxilla, and the teeth preserved there were formed like large fangs. The number of premaxillary teeth distinguished Elasmosaurus from primitive plesiosauroids and most other elasmosaurids, which usually had fewer. The two teeth at the front were smaller than the succeeding ones, and were located between the first two teeth in the dentaries of the lower jaws.
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Skull The holotype specimen, known as GSI/GC/2901–2906, consists of a nearly complete skull and lower jaws, and 72 precloacal vertebrae and ribs preserved in five articulated sections. It was found from Maastrichtian-age calcareous sandstones outcropping in the village of Dholi Dungri in Gujarat. Sanajeh was around in length based on the length of the skull, which is . On the side of the skull there is an opening called the juxtastapedial recess, which is characteristically rectangular.
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The large nostrils are mostly covered by broad, triangular flaps of skin on their anterior margins, leaving small incurrent and excurrent openings. The nasal flaps reach the mouth, obscuring a pair of broad grooves connecting the excurrent openings and the mouth. The long, angular mouth has very long furrows at the corners extending onto both the upper and lower jaws. The small teeth have a narrow central cusp flanked by 1–2 cusplets on both sides.
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The area was part of the Kayenta Formation, about north of Cameron near Tuba City in the Navajo Indian Reservation. Three dinosaur skeletons were found in purplish shale, arranged in a triangle, about long at one side. The first was nearly complete, lacking only the front of the skull, parts of the pelvis, and some vertebrae. The second was very eroded, included the front of the skull, lower jaws, some vertebrae, limb bones, and an articulated hand.
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The specific epithet means "crested" in Latin, a reference to the skull crest. The genus is based on holotype SMNS 56342, a crushed partial skeleton on a slab, found in an abandoned mine near Ankerschlag in Tyrol, in the Norian Seefelder Beds. The counterslab has been lost and with it some of the bone. The fossil consists of the skull, lower jaws, some vertebrae, parts of the limbs and pelvic girdle, and the first part of the tail.
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Restoration Diandongosuchus is known from a nearly complete articulated skeleton (ZMNH M8770) missing most of the tail. The total length of ZMNH M8770 is and the estimated body length of the animal in life is around . The specimen is preserved on its right side, with the underside of the lower jaws and the trunk showing. It was prepared out of a limestone slab to reveal details on the left side of the skeleton, many of which are better preserved.
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Inside the lacrimal bones were depressions that may have held glands, such as salt glands. Within the maxillae were sinuses that were better developed than those of more basal theropods such as Ceratosaurus and Marshosaurus; they may have been related to the sense of smell, perhaps holding something like Jacobson's organs. The roof of the braincase was thin, perhaps to improve thermoregulation for the brain. The skull and lower jaws had joints that permitted motion within these units.
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L. auderiense Described by Heinz Tobien in 1962 based on a series of lower jaws from the Lutetian faunal stage. Tobien also uncovered a small skeleton he defined as a paratype of the species, but Storch and Lister proved in 1985 that, in fact, the skeleton did not even belong to the genus Leptictidium. It was the smallest species of all and was only sixty centimetres long. Several skeletons have been found at the Messel pit.
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The tip of the lower jaws is somewhat curved to below. However, its uniqueness is conditional on Aerotitan not having such a curved tip. This latter pterosaur was originally described as not having one but the authors, while studying Mistralazhdarcho, concluded that the Aerotitan description was likely mistaken and that its curved holotype did not represent the middle of the jaws but their front end. Additionally, a unique combination was given of traits that in themselves are not unique.
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The lower jaws, lacking a keel, have a length of . They are about as tall as the snout and have a pointed tip. The jaws are lined with long conical pointed teeth, up to in length, slightly recurved and more or less oriented vertically. The describers estimated there were fifteen teeth in the upper jaw and seventeen in the lower jaw for a total of sixty-four, which closely matches the number of sixty-two actually found.
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In terms of appearance, dogfish sharks have grayish-brown skin with white dots that becomes paler (almost white) around the belly region. These sharks are characterized by teeth in upper and lower jaws similar in size; a caudal peduncle with lateral keels; the upper precaudal pit usually is present; and the caudal fin is without a subterminal notch. They are carnivorous, principally preying upon organisms smaller than themselves. Some of their prey include herring, mackerel, and capelin.
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Afrovenator is known from a single relatively complete skeleton, holotype UC OBA 1, featuring most of the skull minus its top (likewise the mandible, or lower jaws, are lacking apart from the prearticular bone), parts of the spinal column, partial forelimbs, a partial pelvis, and most of the hind limbs. This skeleton is housed at the University of Chicago. The generic name comes from the Latin afer, "African", and venator, "hunter". There is one named species, Afrovenator abakensis.
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The generic name is derived from Mandarin sha mo, "sand desert", the Chinese name for the Gobi. The specific name means "protected by a shield" in Latin, a reference to the body armour. Shamosaurus is known from the holotype PIN N 3779/2, collected from the Dzunbain Formation, equivalent to the Khukhtekskaya Formation and dating from the Aptian-Albian, about 115 million years old. It consists of a complete skull, lower jaws and partial postcranial skeleton with armor.
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The lower jaws of Brachysuchus are expanded at the tip to form a large bulge, holding the creature's largest tusks. The surface of this part of the bone has a wrinkled look, with many blood vessels running through it. In the lower jaw, there are three tusks in each side of this protuberance. Behind this part the jaws have fused together for a little under half their length before diverging after thirty-one of forty-six post- protuberance teeth.
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The specific name refers to a provenance near Tharmis, the ancient Dacian name of Alba Iulia. The holotype, PSMUBB V651a, b, was found in a layer of the Șard Formation dating from the latest Maastrichtian, sixty-six million years old. It consists of two fused premaxillae of the snout (PSMUBB V651a) and a piece of the symphysis of the lower jaws (PSMUBB V651b). Both parts were assumed to have belonged to a single individual, perhaps a subadult animal.
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The age of this formation is disputed; it could be as old as the Aptian but also as young as the Campanian. The holotype consists of a partial skeleton with skull. It contains the snout, a quadrate bone, the lower jaws, two neck vertebrae, four back vertebrae, the breastbone, belly ribs, the right shoulderblade, two humeri, a radius, two thighbones, a shinebone, the left ilium, the right pubic bone and the left ischium. The skeleton is not articulated.
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The line of the mouth is slightly indented at the center. The upper and lower jaws both contain 56-68 tooth rows; the teeth are blunt and arranged with a quincunx pattern. A transverse row of 5 papillae are present on the floor of the mouth. The pelvic fins are distinctive, being over twice as long as wide with a gently sinuous trailing margin, and tapering to an acute tip that sometimes extends past the disc.
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Since its preserved remains consist of only the two lower jaws, no one can ascertain its cause of death. The researchers were left wondering whether the presence of the ameloblastoma could have contributed to its death. From modern examples, we know that predators often target weak or injured individuals of the herd. The tumor in this dinosaur had not developed to its full extent at the moment it died, but it could have indirectly contributed to its early demise.
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Rattlesnakes are believed to require at least their own body weight in water annually to remain hydrated. The method in which they drink depends on the water source. In larger bodies of water (streams, ponds, etc.), they submerge their heads and ingest water by opening and closing their jaws, which sucks in water. If drinking dew, or drinking from small puddles, they sip the liquid either by capillary action or by flattening and flooding their lower jaws.
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The jaws are quite large, lined with small teeth, and several types are notable for being able to consume fish larger than themselves. Some species in families Eurypharyngidae and Saccopharyngidae are bioluminescent. Like other eels, saccopharyngids have leptocephalus larvae. However, these larvae also have a number of unusual characteristics, such as remarkably deep bodies in the Cyematidae, long lower jaws in the Eurypharyngidae, and unique pigmented swellings at the ends of the gut in Saccopharyngidae and Eurypharyngidae.
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Rodents (from Latin rodere, "to gnaw") are mammals of the order Rodentia, which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents; they are found in vast numbers on all continents except Antarctica. They are the most diversified mammalian order and live in a variety of terrestrial habitats, including human-made environments. Species can be arboreal, fossorial (burrowing), or semiaquatic.
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It consists of elements of the postcrania. A considerable part of the skeleton is known but not the skull or the lower jaws. The body length has been estimated at twelve metres. In 1991 Ralph Molnar renamed Euhelopus zdanskyi to Tienshanosaurus zdanskyi,Molnar, R. E., 1991, "Fossil Reptiles in Australia", In: Editors P. Vickers-Rich, J. M. Monaghan, R. F. Baird and T. H. Rich with the assistance of E. M. Thompson and C. Williams, Vertebrate Palaeontology of Australasia.
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The genus is characterized by one autapomorphy: submental crests, the more or less pronounced cartilage extensions on the lower jaws. Within the genus, one clade has been identified, the "short-tailed" Lycodes that are associated with shallower depths (0–1200 m) than the long-tailed species (3–3000 m). Short tail might represent an adaptation to shallow, Arctic waters; the clade includes many Arctic endemics. In contrast, the long-tailed species do not form a monophyletic group.
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There are short but deep furrows at the corners of the mouth on both jaws. The tooth rows number 49–60 and 49–56 in the upper and lower jaws respectively. Each tooth has a single narrow, upright cusp; the upper teeth are slightly broader and flatter than the lower teeth, with serrated rather than smooth edges. The body is robustly built, with large, broad, paddle-like pectoral fins that originate under the fifth gill slit.
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Upeneus moluccensis has an elongated body which has a sub-cylindrical anterior portion which becomes compressed towards the tail with two dorsal fins which are well separated, with the second dorsal fin directly above the anal fin. The caudal fin is deeply forked. The chin bears a pair of barbels which do not extend past the margin of the preoperculum. The upper and lower jaws, the palatine and the vomer are covered in brush-like or villiform teeth.
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Anderson, ME, Leslie RW, Review of the deep-sea anglerfishes (lophiiformes: ceratioidei) of southern Africa. Ichthyological Bulletin 70-:1-32, 2001. read online Based on finding empty stomachs in captured free-living males, scientists think linophrynid males are unable to feed during their free-living stage after metamorphosis. Also, the “short and stout” denticulars of the upper and lower jaws of these males do not seem suitable for prey capture, and the alimentary canal is undeveloped.
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No mandibles were preserved with the holotype specimen and therefore dentition of the lower jaws could not be determined. The overall width of the skull is broad and having widely separated parietal crests. In addition, the zygomatic arches are deepened and expanded below and behind the eye socket, contributing to the wide skull shape, which is very similar to other entelodonts. The rear portion of eye socket is closed and situated directly above the last two molars.
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The closely set very sharp and firmly anchored teeth lined up along the upper and lower jaws acted together like sharp serrated scissors. The ventral extension of the upper jaw deep unto the sides of the lower jaw made the jaws perform like meat slicers. Saurocephalids were powerful and ferocious predators with powerful jaws capable of slicing and biting off large chunks of meat from their potential prey items. No doubt, fish was on top of the diet list.
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Both lived during the Cenomanian stage of the Late Cretaceous. The skulls of stomatosuchids are said to be platyrostral because they have unusually flattened, elongate, duck- shaped craniums with U-shaped jaws. This platyrostral condition is similar to what is seen in the "nettosuchid" Mourasuchus, which is not closely related to stomatosuchids as it is a more derived alligatoroid that existed during the Miocene. Lower jaws of Laganosuchus thaumastos Unlike Mourasuchus, stomatosuchids have jaws that are less strongly bowed.
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They are still able to absorb heat through this armour, as a network of small capillaries allows blood through the scales to absorb heat. The osteoderms are highly vascularised and aid in calcium balance, both to neutralize acids while the animal cannot breathe underwater and to provide calcium for eggshell formation. Crocodilian scales have pores believed to be sensory in function, analogous to the lateral line in fishes. They are particularly seen on their upper and lower jaws.
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Although being toothless clearly places Argentinadraco in the Dsungaripteroidea sensu Kellner, more specifically within the Azhdarchoidea, its precise classification within this group is more elusive. Lower jaws of the Thalassodrominae, Chaoyangopteridae, and Azhdarchidae tend to be either very similar or radically divergent within the same group. The proportions of at least the front portion of the lower jaw of Argentinadraco resembles those of the azhdarchid Zhejiangopterus, and the chaoyangopterids Chaoyangopterus and Shenzhoupterus. Argentinadraco bears differences, however, from all three groups.
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Their most obvious external differences from alligators are visible in the head. Crocodiles have narrower and longer heads, and more V-shaped than U-shaped snouts. The alligator's upper jaw is wider than its lower jaw, and the teeth in the lower jaw fit into small depressions in the upper jaw. The upper and lower jaws of the crocodiles are the same width, and teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed.
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The upper and lower jaws contain 14–15 and 12–14 tooth rows on either side respectively; in addition, there are one or two rows of small teeth at the upper and lower symphyses (jaw midpoints). The upper teeth have a single narrow, smooth-edged central cusp, flanked on both sides by very large serrations. The lower teeth are narrower and more upright than the uppers, and may be smooth to finely serrated. The five pairs of gill slits are fairly long.
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The teeth are curved to the back, have three roots and are robust. They are limited to the anterior ends of the jaws; there are 28 teeth in the upper jaws and 26 in the lower jaws for a total of 54. Most elements of the postcranial skeleton are known, with the exception of some cervical vertebrae, the ribs, the tail and the two most extreme phalanges of the wing finger.Xiaolin Wang, Kellner, A.W.A., Zhou Zhonghe, and de Almeida Campos, D. (2005).
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The Rewan Formation corresponds to the Induan age at the very beginning of the Triassic Period, about 251 million years ago, when life had only begun to recover from the Permian-Triassic extinction. An additional specimen was also recovered from the same site, although it was not closely associated with the holotype. This specimen, QMF 6676, consisted of a portion of the snout and lower jaws. None of the bones preserved in this specimen overlapped with those preserved in the holotype.
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Bones of the palate (roof of the mouth), such as the vomers, palatines, ectopterygoids, and pterygoids, are poorly preserved, but similar to those of other Devonian stem-tetrapods (in terms of both shape and dentition) when visible. A sliver of bone near the cheek region may represent a branchial element (gill bone). Preserved fragments of the shoulder girdle resemble those of Ichthyostega, such as smooth clavicles and a pointed rear stalk of the interclavicle. The lower jaws were thick and well-preserved.
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Size of Leshansaurus qianweiensis The holotype (QW 200701) was found in 2007. It is a fairly complete skeleton consisting of a partial skull and lower jaws, seven cervical vertebrae, twelve dorsal vertebrae, five sacral vertebrae, two caudal vertebrae, and much of the hind limbs and hands. A second specimen (QW 200702), an isolated femur from a juvenile, has been designated as the paratype. Leshansaurus qianweiensis was named and described in 2009 by Li Fei, Peng Guangzhao, Ye Yong, Jiang Shan, and Huang Daxi.
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The holotype, UFRGS-PV-1099-T, has been found in a layer of red mudstone of the Candelária sequence dating from the Carnian. It consists of a partial skeleton with skull. It contains the lower parts of the skull, the lower jaws, nine back vertebrae, three sacral vertebrae, two tail vertebrae, ribs, belly ribs, chevrons, both ilia, the right pubic bone, both thighbones, both shinbones, both calfbones, and the left foot. The skeleton was partly articulated but has been damaged by erosion.
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The first, holotype specimen of Noripterus (IVPP V.4062, type locality IVPP 64045) preserved the front part of the skull and lower jaws, vertebrae, and partial limbs and pelvis. Noripterus was quite similar to the contemporaneous Dsungaripterus, though it was estimated to be a third shorter. It has long narrow neck vertebrae and, like Dsungaripterus, a crest and no teeth in the front of the lower jaw. The teeth that are present are well-developed and spaced fairly far apart.
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The specimen IGM 100/50 consists of a partial maxilla, scapulocoracoid and manual ungual, and specimen IGM 100/51 compromises a fragmentary skull with lower jaws and other elements, incomplete ilium, and metatarsals of the right foot. These fossils were found in Outer Mongolia. Iren Dabasu and Bayan Shireh dinosaur faunas are very similar, so it is not surprising that a species of Alectrosaurus would be found there. Furthermore, several partial skeletons found in both Inner and Outer Mongolia might belong to Alectrosaurus.
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Muroids are most closely related to the Dipodidae, a smaller group of rodents that includes the jerboas, birch mice, and jumping mice.Carleton and Musser, 2005, p. 749 Jerboas have a dental formula of , including incisors in the upper and lower jaws, three molars in the upper and lower jaw, and in most species a small premolar (the fourth upper premolar, P4) in the upper jaw only.Ellerman, 1940, p. 561 In contrast, all muroids lack the P4,Carleton and Musser, 1984, p.
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The type species, Chrysocetus healyorum, is based on a single subadult specimen from the late middle or early late Eocene of Orangeburg County, South Carolina (, paleocoordinates ).. Retrieved April 2013. The holotype, SCSM 87.195, consists of a partial skull with lower jaws, ten teeth, and the hyoid apparatus; 21 vertebrae, some ribs and a sternum; a partial left forelimb; and partial innominates. A second species, Chrysocetus fouadassii, is known from Bartonian-age deposits in the Western Sahara.Philip D. Gingerich and Samir Zouhri (2015).
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It contains a partial skull with lower jaws, three neck vertebrae, three back vertebrae, a piece of a sacral vertebra, four partial tail vertebrae, ribs, the lower end of a thighbone, the upper ends of a shinbone and calf bone, a second metatarsal and three toe phalanges. The paratype, specimen IGM 100/984, is the skull found in 1996, of which only the snout has been preserved. Both specimens are of adult individuals. In 2003, the skeleton was described in detail.
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Skull in side view (top) with interpretive diagram (bottom) The skull includes most of the and , the bones of the , as well as the lower jaws and parts of the upper jaws, and is therefore the most complete skull of a dicraeosaurid known to date. The middle section of the skull is not preserved. Its overall built was gracile. All bones that surround the (eye opening) are preserved, except for the , which would have formed the lower margin of the opening.
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Ichthyornis is notable primarily for its combination of vertebrae which are concave both in front and back (similar to some fish, which is where it gets its name) and several more subtle features of its skeleton which set it apart from its close relatives. Ichthyornis is perhaps most well known for its teeth. The teeth were present only in the middle portion of the upper and lower jaws. The jaw tips had no teeth and were covered in a beak.
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ATN pain can be described as heavy, aching, stabbing, and burning. Some sufferers have a constant migraine-like headache. Others may experience intense pain in one or in all three trigeminal nerve branches, affecting teeth, ears, sinuses, cheeks, forehead, upper and lower jaws, behind the eyes, and scalp. In addition, those with ATN may also experience the shocks or stabs found in type 1 TN. Many TN and ATN patients have pain that is "triggered" by light touch on shifting trigger zones.
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Mythunga is known from a partial skull, holotype QM F18896 found in April 1991 by Philip Gilmore in marine rocks of the late Albian-age Toolebuc Formation at Dunluce Station west of Hughenden, Queensland. Only the middle snout and corresponding parts of the lower jaws are known, including the rear of a left premaxilla, the lower parts of both maxillae, the rear dentaries and a right splenial. They were three-dimensionally preserved, associated in a chalk nodule. It represents a subadult individual.
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Paralichthys dentatus (Linnaeus, 1766), also called a fluke, is a member of the large-tooth flounder family Paralichthyidae. There are typically 5 to 14 ocellated (eye-like) spots on the body. Like most members of the left-eye flounders, they can change the color and pattern of their dark side to match the surrounding bottom and are also capable of rapidly burrowing into muddy or sandy bottoms. The teeth are quite sharp and well developed on both upper and lower jaws.
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Some of the cranial features of Stenaulorhynchus include afrontal bone that is broader than it is long, the presence of a pineal foramen and a lack of ornamention on the jugal bone. Their postorbital The occipital condyles are significantly anterior to the quadrates and the quadrate and articular fit tightly together to form a jaw joint that wouldn't have allowed for much rotation. They area also known for their beak, formed at the front of their upper and lower jaws.
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The Fortescue grunter has a moderately deep, slightly compressed oval body with convex dorsal profile and a largely straight ventral profile. It has an oblique mouth, which reaches as far as the level of the front of the eye. The upper and lower jaws are equipped with conical teeth with the outer row being enlarged and there are no teeth on the roof of the mouth. The body is covered in finely ctenoid and there is a continuous, smoothly curved lateral line.
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The pattern of grooves and ridges on the crest grows more prominent. The snout tip also starts to straighten in side view, no longer curving upwards. The groove in the dentary deepens and lengthens, as well. No change, however, takes place in the number of teeth, the degree of fusion in the symphysis of the lower jaws, or the shape of the postcranial skeleton, as far as can be ascertained, given the fact that the elements behind the skull were not found articulated.
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Skeletal restoration of the P. mongoliensis holotype The skull of Psittacosaurus is highly modified compared to other ornithischian dinosaurs of its time. Extremely tall in height and short in length, the skull has an almost round profile in some species. The portion in front of the orbit (eye socket) is only 40% of total skull length, shorter than any other known ornithischian. The lower jaws of psittacosaurs are characterised by a bulbous vertical ridge down the centre of each tooth.
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Both upper and lower jaws sport a pronounced beak, formed from the rostral and predentary bones, respectively. The bony core of the beak may have been sheathed in keratin to provide a sharp cutting surface for cropping plant material. As the generic name suggests, the short skull and beak superficially resemble those of modern parrots. Psittacosaurus skulls share several adaptations with more derived ceratopsians, such as the unique rostral bone at the tip of the upper jaw, and the flared jugal (cheek) bones.
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This specimen includes part of the torso and pectoral girdle, the left humerus (upper arm bone), both coracoids, right scapula, the sternal plate, neck vertebrae, back vertebrae, ribs, and the posterior part of the skull and lower jaws. Daohugoupterus was named and described in 2015 by Cheng Xin, Wang Xiaolin, Jiang Shunxing and Alexander Wilhelm Armin Kellner. The type and only known species is Daohugoupterus delicatus. The generic name combines a reference to Daohugou with a Latinised Greek πτερόν, pteron, "wing".
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Brachysuchus is an extinct genus of phytosaur known from the late Triassic period (Carnian stage) of Dockum Group in Texas, United States. It is known from the holotype UMMP 10336 is composed of a skull, lower jaws and partial postcranium and from the associated paratype UMMP 14366, nearly complete skull, recovered from the 'Pre-Tecovas Horizon' in the Dockum Group. It was first named by Case in 1929 and the type species is Brachysuchus megalodon. Its closest relative was Angistorhinus.
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The fossils (twenty one in total) include upper and lower jaws, cranial fragments, and the upper and lower parts of a leg bone (tibia). In addition to this, the aforementioned fragment of humerus found thirty years ago at the same site at Kanapoi has now been assigned to this species. In 2006, a new A. anamensis find was officially announced, extending the range of A. anamensis into northeast Ethiopia. Specifically, one site known as Asa Issie provided 30 A. anamensis fossils.
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In fact, the upper temporal fenestrae were very large, forming conspicuous round openings in the top of the rear skull, serving as attachment areas for the powerful muscles that closed the lower jaws. The eye socket was slightly overshadowed in its front part by a brow ridge that has been seen as the prefrontal bone. In 2019, Norman concluded that it was a fused palpebral bone. Behind it, the upper rim of the eye socket was formed by the supraorbital bone.
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Gnatusuchus likely fed on bivalves in oxygen-poor marsh and swamp environments, using blunt teeth to crush their thick shells. Gnatusuchus has a short, rounded snout and shovel-shaped lower jaw, which may have been adaptations for feeding on these bivalves. The teeth at the back of the jaws are large and globular-shaped whereas the front teeth are more peg- like. Gnatusuchus has only 11 pairs of teeth in its lower jaws, far fewer than in most other crocodylians.
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Most of the skull bones were not preserved, with the exception of both lower jaws as well as a toothed maxilla bone. All of the teeth are slender and conical, and their internal structure has shallowly folded enamel unlike almost all other microsaurs. The teeth are largest right behind the tip of the snout and diminish in size towards the back of the mouth. The complete left mandible was 2.6 centimeters (1.0 inches) in length, indicating that the skull was similar in size.
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Size of the type specimen compared with a human Yi qi is known only from a single partial skeleton (holotype specimen STM 31-2) currently in the collections of the Shandong Tianyu Museum of Nature. The fossil was compressed and is visible on a stone plate and a counterplate. It is largely articulated, including the skull, lower jaws, neck and limb bones but lacking most of the backbone, pelvis and tail. Yi was a relatively small animal, estimated to weigh about .
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"Review of the Late Cretaceous nodosauroid Dinosauria: Denversaurus schlessmani, a new armor- plated dinosaur from the Latest Cretaceous of South Dakota, the last survivor of the nodosaurians, with comments on Stegosaur-Nodosaur relationships". Hunteria 1(3): 1-23.(1988). The fossil the species is based on, the holotype DMNH 468, was discovered in a layer of the late Maastrichtian-age Lance Formation of South Dakota. It consists of a skull, lacking the lower jaws, and a number of osteoderms of the body armour.
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Lagrivea is a fossil genus of squirrel from the Middle Miocene of France. The single species, L. vireti, is known from three mandibles (lower jaws) and two isolated teeth. All come from the fissure filling (a fossil deposit formed when a rock fissure filled with sediment) of La Grive L5, part of the La Grive-Saint-Alban complex in Saint-Alban-de-Roche, southeastern France. Lagrivea was a large tree squirrel with flat lower incisors and a large, triangular fourth lower premolar (p4).
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Journal of Morphology, 19, 511–540. Also, the skull has prominent slime canals, which are used for transporting mucus, as well as large external nares. In addition, the upper jaw is relatively weak and thin, used only for holding teeth. Their large jaws could have held many teeth at once, maybe even over 100 on each side of the upper and lower jaws, but the actual number varies constantly over the animal's lifetime due to natural causes such as fighting, eating, disease, etc.
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The specific name honours Dr. Ray H. Marr who has propagated the Society of Vertebrate Paleontology at the SMU. The holotype, SMU 72834, was found in a layer of the Twin Mountains Formation dating from the Aptian. It consists of a partial skeleton with skull. It preserved the cranium with the lower jaws, the vertebral column up to the twenty-third tail vertebra, the shoulder girdle, the left arm, the right humerus, the pelvis, both thighbones, both shinbones and the left calfbone.
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Males tend to be more brightly coloured and are well known for being aggressive towards one another. The wrestling halfbeak, D. pusilla, is widely used in Asia as fighting animals upon which wagers are placed (see Siamese fighting fish). Both sexes have lower jaws (mandibles) that are much longer than the upper ones, and from this comes the "halfbeak" name. Dermogenys feed extensively on small insects, either in the form of aquatic larvae or as flying insects that have fallen onto the surface of the water.
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Once the impressions have been cast, a set of models has been produced that provide the clinician and dental technician with a replica of the upper and lower jaws with which to work in order to produce the final complete denture. An integral part to the construction is to record how the patient is or should be biting, (i.e. the spatial relationship between the maxilla and the mandible) as well as recording all the necessary information for the next stage, the wax try-in.
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The Mongolian paleontologist Altangerel Perle described and named the new genus Segnosaurus in 1979, based on lower jaws and much of the hindlimbs. He also coined the newer Segnosauridae (now synonym of Therizinosauridae) to contain this species. Translated paper In the same year, paleontologist Dong Zhiming described the genus Nanshiungosaurus, but wrongly interpreted the remains to have pertained to some kind of dwarf sauropod. Translated paper In the following year, Barsbold and Perle coined the family Segnosauria (now Therizinosauria) to contain the Segnosauridae and kin.
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Caupedactylus is known from the holotype specimen MN 4726-V, probably found in the Araripe basin in a layer of the Romualdo Formation dating from the Albian, about 110 million years old. It consists of a partial skeleton with a complete skull, lower jaws and a partial postcranial skeleton. The postcrania contain the right shoulder girdle, left coracoid, sternum, right humerus and the proximal part of the first phalanx of the wing finger. It represents and adult individual, which is exceptional for pterosaurs from this formation.
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The fourth tooth in the upper jaw is with a length of 81 millimetres the largest known for any pterosaur. It is exceptional in size compared to the other teeth of Liaoningopterus also, the longest tooth in the lower jaw having a length of 41 millimetres. Tooth length in the specimen is very variable, which the authors explained by the presence of recently erupted replacement teeth. There were twenty pairs of teeth in the upper jaws and thirteen or fourteen pairs in the lower jaws.
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The nasoantorbital fenestra, the large skull opening, is relatively long at 58% of the skull length. The lower jaws have a length of . The skull is similar to that of Istiodactylus, which lived at about the same time in what is now England, especially in the teeth that are compressed side to side and the long fenestra. However, it differs from Istiodactylus in several details, including a significantly lower skull, different jugal and a slight curve to the upper margin of the lower jaw.
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Brygmophyseter is thought to have been long, and it probably had 11 or 12 teeth in the upper and lower jaws. Brygmophyseter is part of a group of macroraptorial sperm whales (often shortened to "raptorial") which tended to be apex predators using their large teeth to catch struggling prey such as whales. It had a spermaceti organ which was probably used for biosonar like in the modern sperm whale. The whale has made an appearance on The History Channel's TV series Jurassic Fight Club.
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The teeth in the lower jaw may have been 20–30% smaller than those in the upper jaw, but few are known, and they are of uncertain maturity. Apart from this, the teeth were identical. Under each active tooth there was a column of nine replacement teeth within the jaw. With 68 columns in the upper jaws and 60 columns in the lower jaws, these so-called dental batteries (also present in hadrosaurs and ceratopsians) comprised a total of more than 500 active and replacement teeth.
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Behind the eyes are crescent-shaped spiracles, which are spaced further apart than the eyes and bear prominent papillae (nipple-shaped structures) along their posterior inner rims. The mouth is wide and terminally placed on the snout, with furrows at the corners and the center of the upper lip forming a rounded arch. The upper and lower jaws contain 10 and 9 tooth rows respectively on either side; the teeth are small, conical, and sharp. The five pairs of gill slits are laterally situated on the head.
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In amphistyly, the palatoquadrate has a postorbital articulation with the chondrocranium from which ligaments primarily suspend it anteriorly. The hyoid articulates with the mandibular arch posteriorly, but it appears to provide little support to the upper and lower jaws. In orbitostyly, the orbital process hinges with the orbital wall and the hyoid provides the majority of suspensory support. In contrast, hyostyly involves an ethmoid articulation between the upper jaw and the cranium, while the hyoid most likely provides vastly more jaw support compared to the anterior ligaments.
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Top and bottom teeth Acrophyseter was estimated to be using the distance between the cheek bones in comparison to the dimensions of Zygophyseter, which is relatively small, being the smallest of the raptorial sperm whales. Unlike the modern sperm whales, A. deinodon had teeth on both its upper and lower jaws. The teeth were robust and deeply set into the roots, particularly the front teeth, the tooth roots were comparatively thick with the thin tooth crown. The front teeth were more conical than the back teeth.
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Faunal assemblages from the upper Horseshoe Canyon Formation, an early Maastrichtian cool-climate assemblage from Alberta, with special reference to the Albertosaurus sarcophagus bonebed This article is one of a series of papers published in this Special Issue on the theme Albertosaurus. Canadian Journal of Earth Sciences, 47(9), 1159-1181. which dates to about 68.5 million years ago. The only known specimen consists of parts of the upper and lower jaws—both premaxillae, a right maxilla, both dentaries—teeth and numerous small fragments.
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Holotype specimen (FSAC-KK 26) Alanqa is known only from five fragments of the front upper and lower jaws, and possibly a neck vertebra, representing the single type species Alanqa saharica. Two of these fragments were first described, but not named, by Wellnhofer and Buffetaut in 1999, and referred to a pteranodontid. Three additional jaw specimens, including a better preserved upper jaw, were described and named by Ibrahim and colleagues in 2010. The jaws were straight and pointed, like those of the azhdarchids Quetzalcoatlus and Zhejiangopterus.
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There are 18-25 and 14-24 tooth rows on either side of the upper and lower jaws, respectively. The teeth have a slender central cusp flanked by a pair of small cusplets; those of adult males are slightly thicker than those of females. The body is fairly compressed from side to side and tapers towards the tail. The two dorsal fins are placed far back: the first originates over the rear of the pelvic fins while the second originates over the midpoint of the anal fin.
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Skull from multiple angles The type species of Anatosuchus is A. minor, in reference to its small body size. The holotype material (MNN GDF603), is a nearly complete skull with articulated lower jaws, belonging to a juvenile. It was discovered from the upper portion of the Elrhaz Formation and lower portion of Echkar Formation, indicating an Early Cretaceous (Late Aptian or Early Albian) age. Another specimen was found later (MNN GAD17) belonging to an adult, which had both the skull and much of the postcranial skeleton.
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The specific name is derived from Latin longus, "long", and Greek kephale, "head". The holotype, ZDM T8001, is a single skull with lower jaws, found in 1981 by researchers from the Zigong Historical Museum of the Salt Industry, in the Xiashaximiao Formation (Bathonian). The skull, of which the left side is severely damaged, is very elongated and flat. The back part is missing; in its preserved state it has a length of 192 millimetres; the total length in a complete state was estimated at 201 millimetres.
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Ranats, known as Con Queecon in their own language, were a species of meter-tall rodents with long, tusk-like incisors jutting from their lower jaws. Though originally from Rydar II, the Ranats there were nearly wiped out by Human colonists in 200 BBY. Three Ranats stowed away on a spice freighter and crash landed on Aralia, where they re- established their species. Ranat tribes lived in large, maze-like tunnel networks, where they raised their young communally and lured intruders into dead ends to be killed.
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The gaps separating the teeth are a slightly wider than the teeth themselves. While it is hard to infer much about the precise arrangement of the teeth in life, the teeth of the upper and lower jaws probably would have been interlocking. Compared to other polycotylids, the teeth are smaller than those of Eopolycotylus, Pahasapasaurus, and Georgiasaurus, and more numerous than those of Trinacromerum (30-38) or Dolichorhynchops (26-30). Most of the diagnostic characteristics in the skull of Mauriciosaurus are found on the palate.
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The color is bright red on the body and fins; many with black and gray mottling on back and sides. On fish shorter than the mottling is much more apparent and the fins are often edged with black. The yelloweye and canary rockfishes are similar in appearance to the vermilion, but the bottom of their lower jaws is scaleless and feels smooth to the touch. The vermilion rockfish has scales on the bottom of the lower jaw which make it rough to the touch.
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Mourasuchus had rows of small, conical teeth numbering around 40 on each side of the upper and lower jaws. Mourasuchus presumably obtained its food by filter feeding; the jaws were too gracile for the animal to have captured larger prey. It also probed the bottoms of lakes and rivers for food. Fossils have been found in the Pebas Formation at the Fitzcarrald Arch of Peru, where it coexisted with many other crocodylians, including the giant gharial, Gryposuchus, and the alligatorid Purussaurus, both of which were around long.
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The type species is S. venezuelensis. Like other gavialoids, Siquisiquesuchus had a long, narrow rostrum on its skull, accounting for approximately 60% of the skull's length. The number of teeth in the premaxillary bones at the tip of the snout is not known, but the maxillae making up most of the rostrum had at least 20 teeth each, and the dentaries of the lower jaws had at least 23. Some details of the described skulls cannot be determined because the sutures are not visible.
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In the skull the eye socket forms the largest opening, larger than the fenestra antorbitalis that is clearly separated from the slit-like bony naris. No bony crest is visible on the rather straight top of the skull or snout. The lower jaws are thin at the back but deeper toward the front where they fuse into the symphysis ending in a toothless point after which the genus has been named. In MBR 1920.16, the mandibula as a whole has a length of 147 millimetres.
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The transverse nuchal crest on the rear skull roof is not very prominent. In the lower jaw the angular bone forms a major part of the lower rim of the outer side opening. The front point of the lower jaw is obliquely protruding to above under an angle of less than 45° with the symphysis, the fused point of the lower jaws. The shelf formed by the symphysis is moderately large, equal to about a fifth to a fourth of the total jaw length.
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247 was low, without elevated rims over the eyes, and was long. The snout was short and pointed compared to Cretaceous alligatorids. Its premaxillae (the bones of the tip of the snout) had five teeth each, while the maxillae (main tooth-bearing bones of the upper jaw) had thirteen teeth each, with the fourth being the largest and the last three having broad flattened crowns. The lower jaws had twenty teeth on each side, and like the upper jaws, the last five had broad crushing crowns.
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Skeletal diagram of MPC 700/17 Tsagantegia was a medium to large-sized ankyosaur, with an estimated length of Genus List for Holtz 2012 Weight Information and weighing about . The skull measures about in length, with a near width of , missing the lower jaws. Unlike other Asian ankylosaurs, in Tsagantegia the caputegulae (cranial ornamentation) are not subdivided into a mosaic of polygons but are amorphous and flattened; they show some degree of symmetry. The quadratojugal, squamosal and orbital horns are poorly preserved, in contrast with other ankylosaurs.
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Isernia la Pineta in Italy is likely to be the same age or slightly younger. Remains of lower jaws are well documented in these three locations, alongside stone artefacts and numerous bones of rhinos, wild cattle, hippos and horses. Since the remains of the trunks do not show human markings, extinction by natural causes can not be ruled out. The clearest proof to date that this animal was among the prey of early humans was provided in 1948 in Lehringen, Germany, near the Aller river.
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M. mccauleyi skull M. mccauleyi was first described and named by Karen A. Ballew in 1989 as a species of Pseudopalatus, on the basis of the holotype UCMP 126999, an incomplete skull, lacking the anterior half of the rostrum, and probably associated lower jaws. The specific name honors John D. McCauley and Mrs. Molly McCauley McLean from Winslow, Arizona, the owners of the land at "Billings Gap" from which the holotype was found. The specimen was originally informally designated as Pseudopalatus "bilingsensis" by Ballew (1986).
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Pentaceratops, like all ceratopsians, was an herbivore. During the Cretaceous, flowering plants were "geographically limited on the landscape" and so it is likely that this dinosaur fed on the predominant plants of the era: ferns, cycads and conifers. It would have used its sharp ceratopsian beak to bite off the branches which were then shredded - leaves, needles and all - by the tooth batteries, providing a self-sharpening continuous cutting edge in both upper and lower jaws. Ultimately the plant material was digested by the large gut.
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The upper and lower jaws of Tyrannosaurus, like those of many dinosaurs, possessed numerous foramina, or small holes in the bone. Various functions have been proposed for these foramina, such as a crocodile-like sensory system or evidence of extra-oral structures such as scales or potentially lips. The vertebral column of Tyrannosaurus consisted of ten neck vertebrae, thirteen back vertebrae and five sacral vertebrae. The number of tail vertebrae is unknown and could well have varied between individuals but probably numbered at least forty.
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Krause et al., 1997, p. 504 Gondwanatheres are a small group of mammals of uncertain phylogenetic affinities known from the late Cretaceous to the Eocene (~56–34 mya) of the Gondwanan continents, known only from teeth and a few lower jaws. Upon their discovery in the 1980s, gondwanatheres were initially thought to be xenarthrans—part of the same group as living sloths, armadillos, and anteaters—but later workers have favored affinities with multituberculates (a diverse group of fossil mammals) or left the relationships of the gondwanatheres open.
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These deposits are 120 million years old, whereas the original specimen was 125 million years old, meaning the age range for this species is 125-120Ma. Archaeorhychus is one of the earliest avialans known to have had a beak, and represents one of the most basal ornithuromorph avialans. The fossils preserved feathers associated with the neck, head and tail regions. The fossils also show grooves and openings/ holes (foramina) on the tips of the upper and lower jaws, suggesting that it supported a horny bill.
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Eilenodon robustus is the type species of Eilenodontinae, a subfamily of Opisthodontia. It and other eilenodonts had very wide and strongly packed teeth as well as a deep jaw for chewing and shredding plant material. It is primarily known from an incomplete pair of lower jaws approximately 5 centimeters (2 inches) long. If the jaws were complete, they would have been about 10 centimeters (4 inches) long, signifying that Eilenodon robustus was among the largest species of rhynchocephalians known, surpassed only by its fellow eilenodont Priosphenodon avelasi.
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Schreber's yellow bat is a large, robust bat, the largest vesper bat in Africa. It has a head-and-body length of about , a tail length of and a fore-arm length of about , females tending to have slightly longer forearms than males. The canines are well-developed, the upper jaw has a single incisor and four cheek teeth on each side, and the lower jaws have no incisors and five cheek teeth. The ears are medium-sized and widely separated, and there is no nose-leaf.
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Similar to males, they have iridescent green or gold speckling, though the speckles are concentrated on the opercles or cleithrum (bone that extends from pectoral fin up to the cranium above the gills). Females' eyes are also dark, and their upper and lower jaws range in color from olive-black to pale yellow. Their abdomens are pale yellowish-green, and their bellies are tinted pink. They also have olive-black lateral stripes and dorsal saddles; the color between the dorsal saddles is amber to pale yellow.
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Peng, G., Ye, Y., Gao, Y., Shu, C.-K., & Jiang, S., 2005, Jurassic Dinosaur Faunas in Zigong, Zigong, Sichuan Scientific and Technological Publishing House, 236 pp The holotype, ZDM 0019, was found in layers of the Upper Shaximiao Formation of Zigong (Sichuan province), which date to the Oxfordian. It consists of a partial skeleton of a probably subadult individual missing the skull (though the lower jaws are present), hind feet, and the tail end. Apart from skeletal elements also plates, spines and scutes have been found.
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The feathers of Sinosauropteryx, a dinosaur with feathers, were used for insulation, making them an exaptation for flight. Features that now appear as adaptations sometimes arose by co-option of existing traits, evolved for some other purpose. The classic example is the ear ossicles of mammals, which we know from paleontological and embryological evidence originated in the upper and lower jaws and the hyoid bone of their synapsid ancestors, and further back still were part of the gill arches of early fish. The word exaptation was coined to cover these common evolutionary shifts in function.
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Kermack, KA. 1988 British Mesozoic mammal sites. Special Papers in Palaeontology, 40:85-93 More than one specimen was given to Buckland, and one of these lower jaws was lost, but found again in 1827 by William Broderip, and thought by Charles Lyell to be evidence that mammals dated from the earliest times without having changed. However, Britain's most esteemed, comparative anatomist Richard Owen later recognized the Stonesfield fossils as being distinct from opossums and from another mammal found in the same rocks, named Amphitherium. The new genus Phascolotherium was given to "D." bucklandi.
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McKillop, James (22 January 1987). "Mob attempted to cut off policeman's head, court told", The Glasgow Herald. A second group surrounded PC Coombes, who sustained a five-inch-long cut to his face, had his neck slit open, and was left with broken upper and lower jaws. he was still suffering the effects of the attack, which the police regard as attempted murder, including constant pain, poor hearing and eyesight, epileptic fits, nightmares, and a memory so poor that he was left unable to read a book or drive.
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Jaw reduction or Mandible angle reduction is a type of surgery to narrow the lower one-third of the face—particularly the contribution from the mandible and its muscular attachments. There are several techniques for treatment—including surgical and non-surgical methods. A square lower jaw can be considered a masculine trait, especially in Asian countries. As a result, whereas square lower jaws are often considered a positive trait in men, a wide mandible can be perceived as discordant or masculine on women, or sometimes in certain men, particularly when there is asymmetry.
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The size of the teeth varies greatly along the length of the jaws, lending Dimetrodon its name, which means "two measures of tooth" in reference to sets of small and large teeth. One or two pairs of caniniforms (large pointed canine-like teeth) extend from the maxilla. Large incisor teeth are also present at the tips of the upper and lower jaws, rooted in the premaxillae and dentary bones. Small teeth are present around the maxillary "step" and behind the caniniforms, becoming smaller further back in the jaw.
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Lower jaws, lower tetrapods–a review based on the Devonian genus Acanthostega. Transactions of the Royal Society of Edinburgh: Earth Sciences, 89(01), 11-46. The loss of the intercranial joint was a direct functional necessity to strengthen the broad and long platybasic skull when the animal was out of the water. The tubular lower jaw of the Elginerpeton, compared to the flat-lamina jaw shape of fishes gave it superior cross-sectional force, required when not supported in an aquatic setting – allowing for opening of the mouth outside of water.
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Some amphibians and reptiles have the ability to regenerate limbs, eyes, spinal cords, hearts, intestines, and upper and lower jaws. The Japanese fire belly newt can regenerate its eye lens 18 times over a period of 16 years and retain its structural and functional properties. The cells at the site of the injury have the ability to undifferentiate, reproduce rapidly, and differentiate again to create a new limb or organ. Hox genes are a group of related genes that control the body plan of an embryo along the head-tail axis.
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Spinosaurids were large bipedal carnivores. Their crocodilian-like skulls were long, low and narrow, bearing conical teeth with reduced or absent serrations. The tips of their upper and lower jaws fanned out into a spoon-shaped structure similar to a rosette, behind which there was a notch in the upper jaw that the expanded tip of the lower jaw fit into. The nostrils of spinosaurids were retracted to a position further back on the head than in most other theropods, and they had bony crests on their heads along the midline of their skulls.
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A specimen first referred to Patagosaurus in 2003, MPEF-PV 1670 (which includes just a lower jaw), is also very similar to MACN CH 933, and differences can be associated with age, so therefore, MPEF-PV 1670 presumably represents adult cranial material. However, the teeth of MACN CH 934 are very different from those of both lower jaws (MACN CH 933 and MPEF-PV 1670), so it can be identified as another sauropod from the same deposit as Patagosaurus. Thus, the taxon only certainly includes PVL 4170, MACN CH 933, and MPEF-PV 1670.
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They may have also been used to attract mates. Bull woolly rhinos were probably territorial like their modern counterparts, defending themselves from competitors, particularly during the rutting season. Fossil skulls indicate damage from the front horns of other rhinos, and lower jaws and back ribs show signs of being broken and re-formed, which may have also come from fighting. The apparent frequency of intraspecific combat, compared to recent rhinos, was likely a result of rapid climatic change during the last glacial period, when the animal faced increased stress from competition with other large herbivores.
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Northeast Region of Brazil, with the discovery sites of three spinosaurine fossil specimens in the Araripe and São Luís-Grajaú Basins marked. From top to bottom: Oxalaia, Irritator, and Angaturama. Commercial fossil-poachers excavated a chalk concretion containing the rear of a large skull with lower jaws near the town of Santana do Cariri in northeastern Brazil. This fossil was acquired by dealers who illegally sold it—fossil trade has been prohibited by law in Brazil since 1942—to Rupert Wild of the State Museum of Natural History Stuttgart, Germany.
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His reasoning was that the teeth of the lower jaw were weakly connected to the bone and liable to break off if used to consume terrestrial food, and he described the beak as weak as well. However, aside from misidentifying several of the skull bones, by chance the lower jaws were missing the walls supporting the teeth from the inside; the teeth were actually well-supported.Lull and Wright, Hadrosaurian Dinosaurs of North America, pp. 43. Cope intended to describe the skeleton as well as the skull, but his promised paper never appeared.
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Bergisuchus is an extinct genus of small sebecosuchian mesoeucrocodylian known primarily from the Eocene Messel Pit in Germany. Few fossils of Bergisuchus have been discovered, only a single incomplete snout, a few partial lower jaws and some teeth. Despite being fragmentary, the jaw bones are enough to indicate that Bergisuchus had a short, deep, narrow snout and serrated teeth, quite unlike the broad flat snouts of modern crocodylians. As with other sebecosuchians, it is likely that Bergisuchus was a fast, terrestrial predator and not an aquatic ambush hunter like modern crocodylians.
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Aegyptopithecus zeuxis was a species that had a dental formula of 2:1:2:3 on both the upper and lower jaws, with the lower molars increasing in size posteriorly. The molars showed an adaptation called compartmentalizing shear, which is where the cutting edges involved in the buccal phase serve to surround basins in such a way that food is cut into fragments that are trapped and then ground during the lingual phase. The canines of this species were sexually dimorphic. The ascending mandibular ramus of this species is relatively broad.
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Ambulocetus swimming The most basal of marine cetaceans, ambulocetids lived in shallow near-shore environments such as estuaries and bays, but were still dependent on fresh water during some stage of their life. Some of the characteristics related to sound transmission found in the lower jaws of modern whales that were absent in pakicetids are present in ambulocetids. They probably swam by paddling their large feet, which is not a very efficient mode of locomotion, suggesting they ambushed rather than chased prey. Ambulocetids had a narrow head with eyes facing laterally.
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Watutia is an extinct genus of fossil kangaroo known from the Pliocene from New Guinea . It is only known from the type species Watutia novaeguineae, known from some fragmentary upper and lower jaws and isolated teeth from the Pliocene Otibanda Formation in the Morobe Province of Papua New Guinea. The closest relative of the genus was possibly Hadronomas, who lived in today's Queensland a few million years earlier. W. novaeguineae was about the size of a large shrub wallaby (Dorcopsis) and differs in some characteristics from the teeth of other kangaroos.
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After the discovery of the holotype of C. nasicornis, a significant Ceratosaurus find was not made until the early 1960s, when paleontologist James Madsen and his team unearthed a fragmentary, disarticulated skeleton including the skull (UMNH VP 5278) in the Cleveland-Lloyd Dinosaur Quarry in Utah. This find represents one of the largest-known Ceratosaurus specimens. A second, articulated specimen including the skull (MWC 1) was discovered in 1976 by Thor Erikson, the son of paleontologist Lance Erikson, near Fruita, Colorado. A fairly complete specimen, it lacks lower jaws, forearms and gastralia.
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The one named species of Anserimimus is called Anserimimus planinychus. The specific name is derived from the Latin planus meaning 'flat', and the Ancient Greek ὄνυξ, onyx, meaning 'claw', in reference to the peculiar flattened claws which characterize the genus.Rinchen Barsbold, 1988, "A new Late Cretaceous ornithomimid from the Mongolian People's Republic", Paleontological Journal 22: 124-127 Hand of ZPAL MgD−I/65 There is only a single specimen of Anserimimus, its holotype IGM 100/300. It consists of a rather complete and articulated skeleton lacking the skull and lower jaws.
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The known teeth of the front part of the lower jaw were large fangs, and the teeth at the back of the jaws appear to have been smaller. The dentition of elasmosaurids was generally heterodont (irregular throughout the jaws), with the teeth becoming progressively smaller from front to back. The maxillae (largest tooth bearing bone of the upper jaw) of elasmosaurids usually contained 14teeth, whereas the dentaries (the main part of the lower jaws) usually contained 17 to 19. The teeth interlocked, and their tooth crowns were slender and rounded in cross-section.
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The site also included a ritual area with stone circles, which also contained ritual objects (included over 200 human-shaped clay figurines), earrings, and human bone fragments. The presence of 138 lower jaws from wild boar indicates that these animals were used as some form of sacrifice, perhaps similar to the iomante ceremony conducted by the Ainu people with black bears. From Site B district, more than 10 buildings with pillar hole rows, surrounded by a moat were discovered. The site included a water reservoir and 49 underground structures which were probably tombs.
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Miniopterus zapfei is a fossil bat in the genus Miniopterus from the middle Miocene of France. First described in 2002, it is known only from the site of La Grive M, where it occurs with another fossil Miniopterus species, the smaller and more common Miniopterus fossilis. M. zapfei is known from five mandibles (lower jaws) and an isolated fourth upper premolar (P4). The fourth lower premolar is more slender than in M. fossilis and the cingulum shelf surrounding the P4 is less well-developed than in living Miniopterus.
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Abydosaurus is one of the few sauropods known from skull material, with the first described complete skull for a Cretaceous sauropod from the Americas. It is also notable for its narrow teeth, as earlier brachiosaurids had broader teeth. Abydosaurus is based on DINO 16488, a nearly complete skull and lower jaws with the first four neck vertebrae. Abundant skull and postcranial bones were found at the same site, including partial skulls from three additional individuals, a partial hip and associated tail vertebrae, a shoulder blade, an upper arm bone, and hand bones.
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The body is slender and of moderate size, and is grey to greyish-brown in colour, with a paler underside. Of the two dorsal fins, the first is larger than the second, and each has a short spine, a white rear margin, and a dark blotch towards the front, which is more distinct in juveniles. The large caudal fin is asymmetrical, with a longer upper than lower lobe. The broad teeth of this species differ between the upper and lower jaws, with the lower teeth being much larger.
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Unlike Eusmilus, Nanosmilus was not equipped with the phalanges on its lower jaws that its later relative Eusmilus has to protect its saber-teeth, and it likely was more vulnerable to tooth breakage due to the lack of this protective adaptation. Despite its small size, Nanosmilus was still more than capable of killing animals as large as modern domestic pigs or deer, indicating it was already a specialist at hunting animals much larger than itself.Martin, L. D. (1991, January). A new miniature saber-toothed nimravid from the Oligocene of Nebraska.
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They are neotenic, although the larval gills are small and functionless at first, and only adults have fully developed gills. Because of this, sirens most likely have evolved from a terrestrial ancestor that still had an aquatic larval stage. Like amphiumas, they are able to cross land on rainy nights. Except for some patches of small teeth on their palates and on the splenial bone on the inner side of their lower jaws, their mouths have lost all dentition and have been replaced with a horny sheath that resembles a beak.
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The upper part was slightly rotated forward, probably permitting some degree of binocular vision. The teeth were long and slender, as opposed to the usually very short teeth seen in other abelisaurids. On each side of the upper jaws there were four premaxillary and twelve maxillary teeth, while the lower jaws were equipped with fifteen dentary teeth per side. In contrast to the robust-looking skull, the lower jaw was shallow and weakly constructed, with the dentary (the foremost jaw bone) connected to the hindmost jaw bones by only two contact points.
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Universal Fish Catalogue The species forms pairs before an elaborate courtship ritual and spawning, the eggs being released well above the seafloor. The Red Roman is of robust build, orange to red in colour, showing a striking white saddle and white bar over the gill cover, with a horizontal blue line linking the eyes. Its canines are prominent and it has several rows of molars in both upper and lower jaws. South African research shows that individuals occupy a territory ranging of , and that the extent is independent of fish size or habitat quality.
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Howesia is an extinct genus of basal rhynchosaur from early Middle Triassic (early Anisian stage) deposits of Eastern Cape, South Africa. It is known from the holotype SAM 5884, a partial skeleton with palate and partial lower jaws and from two paratypes, SAM 5885 and SAM 5886. It was found in the Burgersdorp Formation of the middle deposits of the Beaufort Group (Karoo Basin) and referred to Subzone B of the Cynognathus Assemblage Zone. It was first named by Robert Broom in 1905 and the type species is Howesia browni, named after Alfred Brown.
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In 1923, paleontologist Charles Lewis Camp discovered a bone in the Chinle Formation in what is now Petrified Forest National Park. It was found on top of a Placerias jaw in an area called Crocodile Hill, part of the late Carnian-age Blue Mesa Member of the formation. The bone included the skull and lower jaws of a reptile, but when Camp removed it from the surrounding rock, then it broke apart. Camp described the skull as being long, with a broken rostrum, and thought it belonged to a pterosaur or small dinosaur.
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In 2011, a second specimen was described, PMOL-AP00010, acquired in 2008 by the Paleontological Museum of Liaoning. It consists of a skeleton with lower jaws, of an adult individual.Chang-Fu Zhou and Rainer R. Schoch, 2011, "New material of the non- pterodactyloid pterosaur Changchengopterus pani LÜ, 2009 from the Late Jurassic Tiaojishan Formation of western Liaoning", Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 260: 265-275 The wingspan of the referred specimen was in 2011 estimated at seventy centimetres. Already in 2010, some estimates for the genus had risen to .
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Both the upper and lower jaws have a pair of large canine teeth at the front and there are also 1 to 3 large canines in the middle of the lower jaw There are teeth on the roof of the mouth. The dorsal fin contains 9 spines and 13 to 15 soft rays and it has its origin above the posterior end of the gill cover. The mambranes between the spines of the dorsal fin are not or are only slightly incised. The anal fin has 3 separated spines and 8 soft rays.
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Only a single was present in Ouranosaurus, which projects into the orbit above the eye. The of Ouranosaurus are unique among ornithischians. The bones are unfused suggesting mobility, and at their ends on the top of the skull are rounded domes, which were described by Taquet (1976) as distinct and rugose "nasal protuberances". The snout was toothless and covered in a horny sheath during life, forming a very wide beak together with a comparable sheath on the short predentary bone at the extreme front of the lower jaws.
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A lesser muscle, the musculus depressor mandibulae, used to open the lower jaws, was located at the back of the skull and was connected to a strongly projecting, broad and anteriorly oblique processus paroccipitalis. Ouranosaurus probably used its teeth to chew up tough plant food. A diet has been suggested of leaves, fruit, and seeds as the chewing would allow to free more energy from high quality food; the wide beak on the other hand indicates a specialisation in eating large amounts of low quality fodder. Ouranosaurus lived in a river delta.
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The angular extension (processus angularis) of the lower jaw is bent toward the center. Another feature is the hard palate which, in contrast to the placental mammals' foramina, always have more openings. The teeth differ from that of placental mammals, so that all taxa except wombats have a different number of incisors in the upper and lower jaws. The early marsupials had a dental formula from , that is, per pine half; they have five maxilla or four mandibular incisors, one canine, three premolars and four molars, for a total of 50 teeth.
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The specific name means "fat snout" in Latin. This specimen was an incomplete adult with a 0.9 m (3 ft) wingspan recovered from the Solnhofen strata near Eichstätt. In 1858 Johann Wagner referred the species to Rhamphorhynchus. After recognising the fundamentally different snout shape, Wagner, after previous failed attempts by Leopold Fitzinger and Christoph Gottfried Andreas Giebel, who used preoccupied names, in 1861 named a distinct genus: Scaphognathus, derived from Greek skaphe, "boat" or "tub", and gnathos, "jaw", in reference to the blunt shape of the lower jaws.
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The remains of Gogoselachus were first discovered in 2005 by John A. Long in the Gogo Formation of Kimberly, making it the first known cartilaginous fish from the Gogo formation in over 60 years. The specimen was found inside a broken concretion, and was made up of the complete lower jaws, the shoulder blades, gill-arches, scales and teeth. During the specimen's preparation (dissolving the surrounding limestone with acetic acid), the cartilaginous elements were released surprisingly quickly, meaning that the fish's skeleton was made up of a special kind of mineralized cartilage.
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One of the toughest foes (and eventually allies) of the game series, Elites are a highly intelligent, deeply spiritual species, equally competent as warriors and as communicators, and a core constituent of the Covenant alliance. Known as Sangheili in the fictitious Covenant language, they originate from the planet Sanghelios. They are approximately tall, long-limbed, and muscular, generally with deep blue or purple skin and large, dorsoventrally lengthened heads. The Elites initially had simple mouths, which later developed into pairs of split mandibles substituting for the lower jaws.
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Jaws from adult individuals bearing identical teeth have never been found. Marsh already suggested such teeth were pathological, having formed when the first teeth of the lower jaws by accident grew back-to-back to each other on the mandible suture. Philip J. Currie in 1990 also concluded to a malformation, thinking the flattened side resulted from the tooth remaining attached too long to the inner wall of the tooth-socket. Serrated specimens of the type would thus simply be deviant dromaeosaurid teeth; however, unserrated teeth might represent a separate taxon or taxa.
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It was traded to Italy in 1983 and bought by Borgomanero for his collection. The skull is severely damaged, especially on the top, and was perhaps reconstructed by the fossil dealer. Model in Germany, showing how the jaws where originally reconstructed As shown by a later preparation by the Brazilian Museu Nacional, in the first preparation many serious mistakes were made. The fronts of the snout and of the lower jaws were confused leading to a reconstruction in which the anterior part of the head was upside down.
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The technical distinction between the New World platyrrhines and Old World catarrhines is the shape of their noses. The platyrrhines (from Ancient Greek platu-, "flat", and rhin-, "nose") have nostrils which face sideways. The catarrhines (from Ancient Greek kata-, "down", and rhin-, "nose") have nostrils that face downwards. Catarrhines also never have prehensile tails, and have flat fingernails and toenails, a tubular ectotympanic (ear bone), and eight, not 12, premolars, giving them a dental formula of: , indicating 2 incisors, 1 canine, 2 premolars, and 3 molars on each side of the upper and lower jaws.
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G. pebasensis was named in 2015 on the basis of a nearly complete skull and several lower jaws from the Pebas Formation near Iquitos in Peru. It lived alongside six other species of crocodylians, including two other caimans with crushing dentitions: Kuttanacaiman iquitosensis and Caiman wannlangstoni. The genus name comes from the Quechua word ñatu meaning "small nose" and the species name comes from an Amazonian village called Pebas. A phylogenetic analysis published alongside its initial description placed Gnatusuchus as the most basal member of the clade Caimaninae.
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Ruberodon is an extinct genus of traversodontid cynodonts known from the type and only species Ruberodon roychowdhurii from the Late Triassic of India. Ruberodon was named in 2015 on the basis of several isolated lower jaws found in the Tiki Formation. The lower jaw of Ruberodon has three pairs of incisors, one pair of canines, and 9 pairs of postcanine teeth. The first pair of incisors is enlarged and protrudes forward from the tip of the jaw and there is a gap called a diastema between the canines and postcanines.
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They had a shorter ribcage and larger lungs which allowed more efficient respiration. Their lower jaw comprised a single bone -- the dentary (as opposed to the multiple bones in the jaws of their ancestors, or seven different bones found in reptilian lower jaws). The other bones which once made up the jaw had reduced, and in later mammals would become incorporated into the middle ear, enhancing their hearing. Probably the most important change in the evolution of the first mammals was that their ancestors, the cynodonts, had become warm- blooded.
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Zygophyseter skull (back) next to that of alt=The killer sperm whale skull is behind the skull of the other whale, and is seemingly twice as long Zygophyseter had 28 teeth in the lower jaws and 26 in the upper jaws. The curvature of the teeth increased medially, that is, the teeth in the front of the mouth were straighter than the teeth in the back of the mouth. The back teeth featured more wear than the front teeth. Like Brygmophyseter, it had a relatively small crown, making up only 18% of the tooth.
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Their tails help to offset their balance while moving swiftly through the trees since their tails are about the same length as their head and body size. Sexual dimorphism is very low, with males and females being of about equal sizes. The upper and lower jaws of the Matschie's tree-kangaroos are different too in addition to them being different in body size. The upper jaw has three incisors, one canine, one premolar, and four molars, while the lower jaw has one very sharp incisor, no canines and low crowned molars.
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The generic name means "like a crane" in Chinese. The specific name means "with slender wings". The holotype, JLUM-JZ07b1, was found in fluvial deposits of the lower Yixian Formation, which have a highest possible age of 139 million years and a lowest of 128 million years and thus date from some time in the early Valanginian to early Barremian stage. It consists of a partial skeleton, containing the skull, the lower jaws, a series of five cervical vertebrae, the shoulder girdle and the majority of both forelimbs and hindlimbs.
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The snout tip reaches downwards in front of the lower jaws, so deeply that the roof of the mouth at this point is at a level with the bottom edge of the lower jaw. The fossa antorbitalis, a depression on the side of the maxilla, covers almost the entire outer surface of that bone. The parietal bones are joint at their midline in a crest. The large bone extensions at the back of the skull, the processus paroccipitales, are hanging down below the level of the foramen magnum.
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The specific name honours the Miessler family for its support of the project. The holotype, WYDICE- DML-001, was found in a layer of the middle Morrison Formation dating from the Tithonian. It consists of a partial skeleton containing the rear skull and lower jaws, hyoid bones, five neck vertebrae, the first back vertebra, twelve tail vertebrae, a rib, chevrons, the left shoulder girdle, the right humerus, the left arm, a thighbone piece, and the left and right lower legs minus the right toes. The skeleton was partially articulated, representing a subadult or adult individual.
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Its teeth are highly differentiated between the upper and lower jaws, with the upper teeth small and narrow and the lower teeth large, triangular, and serrated. Its typical length is . Armed with large teeth and a strong bite, the kitefin shark is a powerful, solitary predator that takes many different types of prey, ranging from bony fishes, sharks and rays, to cephalopods, crustaceans, polychaete worms, siphonophores, and possibly carrion. It also takes bites out of animals larger than itself, similar to its smaller relative, the cookiecutter shark (Isistius brasiliensis).
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The surface of the skull roof is covered by raised bumps and ridges, a condition paleontologists E. H. Beaumont and T. R. Smithson describe as "pustular ornamentation". Another distinguishing feature of S. mirus is its dentition; it jaws are lined with hundreds of small, chisel-shaped, closely spaced teeth. These marginal teeth are each about in cross-sectional diameter and form an unbroken row along both the upper and lower jaws. While they point directly downward in the upper jaw, the marginal teeth slant slightly inward (mesially) in the lower jaw.
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Reconstruction of L. ornatus Life restoration with dicynodont prey and speculative hair Lycaenops measured about and weighed up to .Gorgonopsia Like the modern-day wolves from which it takes its name, Lycaenops had a long and slender skull, with a set of dog-like fangs set into both its upper and lower jaws. These pointed canine teeth were ideal for the use of stabbing and/or tearing at the flesh of any large prey that it came upon. Lycaenops most likely hunted small vertebrates such as reptiles and dicynodonts.
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For the most part, Aetiocetus retains a primitive tooth count of 11 upper teeth and 11 lower teeth, abbreviated 11/11. This is interpreted to be the basic mammalian dental formula with 3 incisors, 1 canine, 4 premolars, and 3 molars on both upper and lower jaws. However, A. weltoni and A. polydentatus show variation from the plesiomorphic mammalian dental formula. A. weltoni possesses an 11/12 dentition. True to its name of “many toothed”, A. polydentatus possesses more teeth than any other aetiocetid, and is remarkable in that the number of teeth are asymmetrical.
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Cranial: The upper and lower jaws are covered with sensory pits, visible as small, black speckles on the skin, the crocodilian version of the lateral line organs seen in fish and many amphibians, though arising from a completely different origin. These pigmented nodules encase bundles of nerve fibers innervated beneath by branches of the trigeminal nerve. They respond to the slightest disturbance in surface water, detecting vibrations and small pressure changes as small as a single drop. This makes it possible for crocodiles to detect prey, danger and intruders, even in total darkness.
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The smaller earlier segments were walled off and the animal could maintain its buoyancy by filling them with gas. Thus, the smaller sections of the coil would have floated above the larger sections. Many ammonite shells have been found with round holes once interpreted as a result of limpets attaching themselves to the shells. However, the triangular formation of the holes, their size and shape, and their presence on both sides of the shells, corresponding to the upper and lower jaws, is more likely evidence of the bite of a medium-sized mosasaur preying upon ammonites.
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The external nares were long, narrow and horizontally positioned; the same was true of the larger antorbital fenestrae, a pair of bony openings in front of the eyes. The rear of the skull is poorly known but for a short quadrate bone, which had broad condyles (round protrusions) away from the centre of attachment and—like in the spinosaurid Baryonyx—had a large foramen (opening) separating it from the quadratojugal bone. The lower jaws were greatly elongated and narrow, forming a rigid structure as their dentaries touched each other at the midline, reinforcing the mandible against torsional (bending and twisting) forces.
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The lower jaws were adapted for slicing bites, and it probably captured and manipulated prey with the front part of the jaws. These authors suggested that Giganotosaurus and other allosaurs may have been generalized predators that fed on a wide spectrum of prey smaller than themselves, such as juvenile sauropods. The ventral process (or "chin") of the lower jaw may have been an adaptation for resisting tensile stress when the powerful bite was delivered with the front of the jaws against the prey.Therrien, F.; Henderson, D. M.; Ruff, C. B., 2005, "Bite Me: Biomechanical models of theropod mandibles and implications for feeding".
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The offspring are born with specific dentition that they can use to peel and eat the outer epidermal later of their mother's skin. Young move around their mother's bodies, using their lower jaws to lift and peel the mother's skin while vigorously pressing their heads against her abdomen. To account for this, the epidermis of brooding females can be up to twice the thickness of non-brooding females. Viviparous (developing in the mother) caecilians on the other hand, have specialized fetal dentition which can be used for scraping lipid-rich secretions and cellular materials from the maternal oviduct lining.
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Miniopterus tao is a fossil bat in the genus Miniopterus from the Pleistocene of Zhoukoudian in China. It is known from a number of mandibles (lower jaws), which were initially identified as the living species Miniopterus schreibersii in 1963 before being recognized as a separate species, M. tao, in 1986. Miniopterus tao is larger than living M. schreibersii and has more closely spaced lower premolars and more robust talonids (back groups of cusps) on the lower molars. The back part of the mandible is relatively low and on it, the coronoid and condyloid processes are about equally high.
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In 1934, Chinese paleontologist C.C. Young was the first to describe fossil bats from the fossil site of Zhoukoudian Locality 1, which is famous for Peking Man. However, he did not mention Miniopterus, which was first recorded by Kazimierz Kowalski and Chuan- kuei Li in 1963 in a description of new material from layer 8 of the cave site. They identified the Miniopterus as the widespread living species Miniopterus schreibersii on the basis of 48 mandibles (lower jaws) from layer 8 and reassigned another mandible that had previously been identified as Myotis to Miniopterus.Kowalski and Li, 1963, pp.
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The submandibular glands (previously known as submaxillary glands) are a pair of major salivary glands located beneath the lower jaws, superior to the digastric muscles. The secretion produced is a mixture of both serous fluid and mucus, and enters the oral cavity via the submandibular duct or Wharton duct. Approximately 65-70% of saliva in the oral cavity is produced by the submandibular glands, even though they are much smaller than the parotid glands. This gland can usually be felt via palpation of the neck, as it is in the superficial cervical region and feels like a rounded ball.
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The specific name refers to the Caribbean, Caribe in Spanish. The genus is based on holotype IGO-V 208, a partial but well-preserved uncrushed skull — missing the tip of the snout, teeth, and lower jaws — and fragmentary left wing: the distal end of the ulna, fragments of the radius, and the first and fourth phalanx of the wing finger. The partial skull is seventeen centimeters long (6.7 inches), is preserved in three dimensions, and has a broad roof. The wingspan and length were not estimated by the describers, but it was indicated to be a relatively large form.
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The holotype specimen, JZMP04117, was discovered in the Daohugou Beds of the Tiaojishan Formation in the Inner Mongolia region of China, which dates to about 159–164 million years ago (mya) in the Middle to Late Jurassic. It comprises a partial skeleton including an incomplete skull but well-preserved lower jaws, most of the ribs, the limbs (save for the right hind leg), the pelvis and the tail. The remains are so well preserved that there are elements of its soft anatomy and hair. Castorocauda is a member of the order Docodonta, an extinct group of mammaliaforms.
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In addition, a sculpted model of what the museum felt the skull of this massive creature might look like was placed on the skeleton. This was not a delicate skull like that of Diplodocus, which would later turn out to be more accurate, but was based on "the biggest, thickest, strongest skull bones, lower jaws and tooth crowns from three different quarries". These skulls were likely those of Camarasaurus, the only other sauropod for which good skull material was known at the time. The mount construction was overseen by Adam Hermann, who failed to find Brontosaurus skulls.
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These were by the describers assumed to represent most of the original number, giving a total of twenty-two tooth positions — or twenty if a small element would be a replacement tooth — although it is not certain how they were divided between the upper jaws and the lower jaws. The teeth are elongated, straight, pointed and circular in cross-section. Although it is flattened on the slab, the skull is thought to have been tall at the back with a shortened snout. The eyes are very large relative to the size of the skull, occupying around a third of its total length.
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Dissertation University of Pennsylvania 164 pp However, such a nomen ex dissertatione does not constitute a valid name. The type species Equijubus normani was formally named in an article by You, Luo Zhexi, Neil Shubin, Lawrence Witmer, Tang Zhilu and Tang Feng in 2003. The type specimen or holotype, IVPP V12534, consists of a complete skull with articulated (attached) lower jaws, plus associated incomplete postcrania: nine cervical (neck), sixteen dorsal (back), and six sacral (pelvic) vertebrae. It was found in fluvio-lacustrine sediments of the Middle Grey Unit of the Xinminpu Group, Gonpoquan Basin, Mazong Shan, Gansu Province, China.
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The ciscoes (or ciscos) are salmonid fish of the genus Coregonus that differ from other members of the genus in having upper and lower jaws of approximately equal length and high gill raker counts. These species have been the focus of much study recently, as researchers have sought to determine the relationships among species that appear to have evolved very recently. The term cisco is also specifically used of the North American species Coregonus artedi, also known as lake herring. In previous taxonomic classifications, the ciscoes have been identified as a subgenus Leucichthys of the genus Coregonus.
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In addition to these cranial differences, in 2019 Button and Zanno note that herbivorous dinosaurs followed two main distinct modes of feeding. One of these was processing food in the gut which is characterized by gracile skulls and relatively low bite forces, and the second was oral food processing, characterized by features associated with extensive processing such as the lower jaws or dentition. Segnosaurus was found to be in the former mode, whereas Erlikosaurus was more likely to fall in the second group, further supporting that these two therizinosaurids were separated by a well-defined niche differentiation.
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Characteristic of raptorial sperm whales, Livyatan had functional, enamel- coated teeth on the upper and lower jaws, as well as several adaptations for hunting large prey. Livyatans total length has been estimated to be about , similar to the modern sperm whale (Physeter macrocephalus), making it one of the largest predators to have ever existed. The teeth of Livyatan measured , and are the largest biting teeth of any known animal, excluding tusks. It is distinguished from the other raptorial sperm whales by the basin on the skull, and how it spans the entire length of the snout.
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The symphysis fragment is 88 millimetres long and very straight and narrow, with a lanceolate not-expanded tip and triangular cross-section. It lacks a keel or crest and is convex on top, with a median narrow deep groove not reaching the tip, but flat at the bottom. As far as can be judged from the empty elliptical tooth-sockets, the lower jaws carry at least five pairs of teeth, which are rather large and become more outwards inclining and procumbent towards the front. Aussiedraco is estimated to have been smaller in size than Mythunga, a pterosaur from the same formation.
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Some kalas are shown disgorging vine-like plants, and some serve as the base for other figures. Scholars have speculated that the origin of the kala as a decorative element in Khmer temple architecture may be found in an earlier period when the skulls of human victims were incorporated into buildings as a kind of protective magic or apotropaism. Such skulls tended to lose their lower jaws when the ligaments holding them together dried out. Thus, the kalas of Angkor may represent the Khmer civilization's adoption into its decorative iconography of elements derived from long forgotten primitive antecedents.
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Mandibles (lower jaws) of both species are known. The mental foramen (an opening in the front of the jaw bone) opens towards the labial side of the bone, except in one mandible of A. praeuniversitatis, in which its opening is located higher. There is a well-developed capsular process—a raising in the bone that houses the root of the lower incisor. The masseteric ridges (two ridges on the labial side of the bone that anchor some of the chewing muscles) are joined into a single crest towards the front and reach to a point below the front of m1.
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Lorosuchus is known from the holotype PVL 6219, a nearly complete skull found articulated with the lower jaws and fragmentary postcranial remains. It was collected at the southern end of Medina Range, near the El Cadillal Lake from the Río Loro Formation, dating to the Thanetian or the Selandian stage of the Middle to Late Paleocene, about 61.7 to 55.8 million years ago.Lorosuchus at Fossilworks.org Lorosuchus is characterized by a unique combination of characters, including five autapomorphies such as an elevated narial rim and the presence of a crest on the anteromedial margins of both premaxillae.
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In all other known theropods, the second finger is the longest. At least two species, Yi and Ambopteryx, also had a long "styliform" bone growing from the wrist, which, along with the third finger, helped support a bat-like wing membrane used for gliding. This use of a long finger to support a wing membrane is only superficially similar to the wing arrangement in pterosaurs, even though it is physically more bat-like. Other features shared within the group include short and high skulls with down turned lower jaws and large front teeth, and long arms.
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Acrophyseter, together with Brygmophyseter, Livyatan, and Zygophyseter, belong to a group of macroraptorial sperm whales, which have adaptations to hunting large prey. They all have large, deeply rooted teeth coated in enamel in both the upper and lower jaws, unlike the modern sperm whale (Physeter macrocephalus) which lacks enamel and teeth in the upper jaw. Raptorials are thought to have either evolved these adaptations from a basilosaurid-like ancestor or independently once or twice within the group. The extinct subfamily Hoplocetinae has been proposed to house this group, alongside the genera Scaldicetus, Diaphorocetus, Idiorophus, and Hoplocetus.
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The surface of the maxilla is profusely sculpted with ridges and grooves, a feature that clearly distinguishes it from Iberosuchus. The lower jaws are mostly only known from incomplete dentaries (as well as part of the splenial), and their surfaces are as similarly strongly sculpted as the upper jaws. The teeth are relatively narrow and serrated (ziphodont), similar to those of predatory theropod dinosaurs and unlike the conical teeth of modern crocodylians. Few teeth themselves are preserved, but they include a very large and prominent serrated 'pseudocanine' that fits into the notch of the upper jaw.
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E. grangeri skull Several species of Embolotherium have been named, including Embolotherium andrewsi, Embolotherium grangeri, Embolotherium louksi, Embolotherium ultimum, Embolotherium ergilensi, and Embolotherium efremovi. However, only two species, Embolotherium andrewsi and Embolotherium grangeri, appear to be valid. Other supposed species of Embolotherium are probably synonymous with these two species and were originally based on juvenile skulls, poorly preserved fossil material, or specimens that are not significantly different from either E. andrewsi or E. grangeri. 207x207pxAnother genus of brontothere, Titanodectes, which was named for several lower jaws found in the same sedimentary deposits as Embolotherium, probably represents the same beast as Embolotherium grangeri.
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Selenosteidae is a family of small to large-sized arthrodire placoderms from the Late Devonian. With the exception of the Chinese Phymosteus, selenosteids lived in shallow seas in what is now Eastern North America (the Cleveland Shale), Eastern Europe (Holy Cross Mountains, Poland, and the Kellwasserkalk fauna of Bad Wildungen), and Northeastern Africa (the Anti-Atlas Mountains, Morocco). Selenosteids have, in cross section, a rounded body, a blunt snout, and tremendous orbits. The lower jaws were slender, the inferognathals usually either being finely serrated, or adapted for crushing, though, in Draconichthys, the inferognathals had long prongs for seizing prey.
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Enchodus species were small to medium in size. One of the genus' most notable attributes are the large "fangs" at the front of the upper and lower jaws and on the palatine bones, leading to its misleading nickname among fossil hunters and paleoichthyologists, "the saber-toothed herring". These fangs, along with a long sleek body and large eyes, suggest Enchodus was a predatory species. The largest-known species of Enchodus is E. petrosus, remains of which are common from the Niobrara Chalk, the Mooreville Chalk Formation, the Pierre Shale, and other geological formations deposited within the Western Interior Seaway and the Mississippi Embayment.
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Dating carried out by the Max Planck Institute for Evolutionary Anthropology in Leipzig revealed that the Jebel Irhoud site and its Homo sapiens fossils were far older than first thought. Fresh excavations revealed the remains of at least five people and a number of stone tools. The finds included part of a skull, a jawbone, teeth, and limb bones that had come from three adults, a juvenile, and a child aged about seven and a half years old. The bones looked similar facially to those of humans today, but had much larger lower jaws and elongated braincases.
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Xinpusaurus is a thalattosaur, a group of triassic marine reptiles with long, paddle-like tails and short legs with independently movable digits. Specifically, it is a member of the group thalattosauroidea, which are characterized by their downturned premaxillae. Xinpusaurus had a short neck, a massive quadrate, and one of the few braincases preserved in thalattosaurs. The lower jaws of this genus show two different forms of dentary-surangular sutures, either a v-shaped suture with the surangular cutting into the dentary from the side (type 1) or an oblique suture with the surangular underlying the dentary (type 2).
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The specific name refers to his family name. Zhenyuanlong was one of eighteen dinosaur taxa from 2015 to be described in open access or free-to-read journals. The holotype, JPM-0008, was found in the Sihedang locality of Jianchang County of northeastern China's Yixian Formation, which dates from the Aptian age of the Early Cretaceous (125–113 million years ago). The holotype specimen is represented by its sub-adult status, its nearly complete and articulated skeleton lacking only half of the tail, its well preserved skull and lower jaws, and its preservation of vaned feathers on the arms and tail.
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A restoration of the head of Megaraptor, based on the juvenile specimen described in 2014 No megaraptoran fossil is known to preserve a complete skull, although skull material is known for several taxa. Aerosteon, Orkoraptor, and Murusraptor preserve several bones of the rear part of the skull, lower jaws are known from Australovenator, and a juvenile specimen of Megaraptor described in 2014 preserved much of the snout as well as parietal fragments. Teeth have been found in many genera. Collectively, megaraptorans can be reconstructed as having a long, lightly built skull with many relatively small teeth.
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The horizontally oval eyes are equipped with rudimentary nictitating membranes (protective third eyelids) and placed rather high on the head, with a thick ridge running under each. The mouth is wide and arched, with short furrows at the corners extending onto both jaws; the upper teeth are exposed when the mouth is closed. There are 18-30 and 13-26 tooth rows on either side of the upper and lower jaws respectively. The teeth have a narrow central cusp with a pair of small lateral cusplets; those of adult males are slightly more curved than those of females.
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They were first identified as a pliosaurid skull by Richard Edmonds, Earth Sciences Manager for Dorset and East Devon Coast World Heritage Site Team. Due to its large size and completeness, the specimen gained extensive media coverage, and its acquisition was announced publicly in October 2009. Additional elements were later donated by Patrick Clarke and purchased from Shirley Swaine. DORCM G.13,675 went on display in Dorchester County Museum in July 2011, after being in preparation between March 2010 and March 2011. Preparation of the lower jaws took 200 hours and a further 365 hours were needed to complete preparation of the skull.
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Heavily restored skull of S. ferox in the Field Museum The skull of Sphenacodon is very similar to that of Dimetrodon. It is narrow from side to side and vertically deep, with an indented notch at the front of the maxillary bone in the upper jaw. The upper and lower jaws are equipped with an array of powerful teeth, divided into sharp pointed "incisors" [precaniniforms], large stabbing "canines" [caniniforms], and smaller slicing back teeth [postcaniniforms]. The orbit is set high and far back with a single opening (temporal fenestra) behind and partly below the eye, a characteristic of synapsids.
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Howler monkeys are found only in the rainforests of the Americas ranging through eastern Bolivia, southern Brazil and Paraguay, and northern Argentina. They are the largest monkey in Latin American rainforests growing as high as up to three feet tall when standing and weigh from eight to twenty-two pounds. They have big necks and lower jaws, where their super-sized vocal cords are housed. They live high in the trees and hang from branches by their tails who tend to move in troops of about 18 monkeys deep; spending most of their time sleeping and grooming each other.
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Holes have been found in fossil shells of some ammonites, mainly Pachydiscus and Placenticeras. These were once interpreted as a result of limpets attaching themselves to the ammonites, but the triangular shape of the holes, their size, and their presence on both sides of the shells, corresponding to upper and lower jaws, is evidence of the bite of medium-sized mosasaurs. Whether this behaviour was common across all size classes of mosasaurs is not clear. Virtually all forms were active predators of fish and ammonites; a few, such as Globidens, had blunt, spherical teeth, specialized for crushing mollusk shells.
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Procumbent teeth project forward from the tips of the upper and lower jaws, which is highlighted in the species name chauliodis that roughly means "buck-toothed". Daemonosaurus is unique among Triassic theropods because it has an unusually short snout, and all other early theropods had long heads and jaws. Like the coelophysoids, Daemonosaurus has a kink in its upper jaws, between the maxilla and the premaxilla. The proportionately large orbit, the short snout, and the apparent lack of fusion between the bones of the braincase suggest that the holotype specimen CM 76821 may be an example of a juvenile dinosaur.
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The Aden Gulf torpedo has a thick, nearly circular pectoral fin disc wider than long, with a nearly straight anterior margin. The eyes are fairly small and immediately followed by large, rounded spiracles; each spiracle has a subtly raised rim that bears a series of tiny knob-like papillae along the posterior margin. The nostrils are surrounded by folds, and have a short and wide curtain of skin between them that reaches the mouth. The teeth are arranged with a quincunx pattern and number 33-47 rows in the upper jaw and 32-39 rows in the lower jaws.
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Lateral view of the lower jaws of P. bavaricum at Naturkundemuseum Ostbayern Prodeinotherium was the size of the present Asian elephant, about at the shoulders, but differing from elephants by lacking upper tusks and instead possessing downward-facing lower tusks. In appearance and many characters, it was like Deinotherium, but differed in being of smaller size, having shorter fore limbs, and also in various details in the shape and form of the teeth.Sanders, W. J., Kappelman, J. & Rasmussen, D. T., 2004 New large-bodied mammals from the late Oligocene site of Chilga, Ethiopia. Acta Palaeontologica Polonica Vol.
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The ingestion of the paint by the women, brought about while licking the brushes, resulted in a condition called radium jaw (radium necrosis), a painful swelling and porosity of the upper and lower jaws that ultimately led to many of their deaths. This led to litigation against U.S. Radium by the so-called Radium Girls, starting with former dial painter Marguerite Carlough in 1925. The case was eventually settled in 1926 and several more suits were brought against the company in 1927 by Grace Fryer and Katherine Schaub. The company did not stop the hand painting of dials until 1947.
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The southern black bream has a deep, moderately compressed body, with both the dorsal and ventral profiles equally curved. The mouth is of moderate size in comparison with the body, and contains six curved, peg like incisors in the front of both upper and lower jaws. The molars are set in series of four or five on each side of the upper jaw, and in series of three or four on the sides of the lower jaw, becoming smaller in size anteriorly. The body is covered with large scales, which may be cycloid or weakly ctenoid in shape.
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It consists of a skull with lower jaws. In 1915 Nopcsa referred his species to the genus Orthomerus, as an Orthomerus transsylvanicus.F. Nopcsa, 1915, "Die dinosaurier der Siebenbürgischen landesteile Ungarns", Mitteilungen aus dem Jahrbuche der Königlich-Ungarischen Geologischen Reichsanstalt 23: 1-24 However, since the 1980s, Orthomerus has been considered a nomen dubium, leading to a revival of the name Telmatosaurus. Fragmentary hadrosauroid material from Spain, France and Germany, that had been referred to Orthomerus, is now often assigned to Telmatosaurus, but an identity is hard to prove; the same is also true of many Romanian fragments and eggs.
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Cervical vertebra in multiple views In 1923, during the American Museum of Natural History expedition by Roy Chapman Andrews to Inner Mongolia, Peter Kaisen discovered numerous theropod remains in three quarries. They consist of the largely disarticulated remains of several individuals and material of the skull and the lower jaws is lacking. These were named and shortly described by Charles Whitney Gilmore in 1933 as a new species of Ornithomimus: Ornithomimus asiaticus. The specific name refers to the Asian provenance. The species was placed in the new genus Archaeornithomimus by Dale Russell in 1972, making Archaeornithomimus asiaticus the type species of the genus.
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It has also been suggested that heterodontosaurs and other basal (or "primitive") orhithischians had lip-like structures like lizards do (based on similarities in their jaws), rather than bridging skin between the upper and lower jaws (such as cheeks). The proportionally large lower temporal fenestra was egg-shaped and tilted back, and located behind the eye opening. The elliptical upper temporal fenestra was visible only looking at the top of the skull. The left and right upper temporal fenestrae were separated by the sagittal crest, which would have provided lateral attachment surfaces for the jaw musculature in the living animal.
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Kaprosuchus is known by only a single skull, discovered by the palaeontologist Paul Sereno in 2009. The prehistoric crocodile had oversized tusks embedded toward the front of its upper and lower jaws, inspiring Sereno's affectionate nickname, the BoarCroc. Like many crocodiles of the Cretaceous period, Kaprosuchus was not restricted to river ecosystems; judged by its long legs and impressive dentition, this four-legged reptile roamed the plains of Africa much in the style of a big cat. In fact, with its big tusks, powerful jaws and span, Kaprosuchus may have been capable of taking down comparably sized herbivorous (or even carnivorous) dinosaurs.
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The inner morphology of the beak is similar to that of the lesser flamingo, where the upper and lower jaws contain lamellae which filter the food. In both the upper and lower jaw, the proximal portion of the bill contains lamellae that are ridge-like with a curvature and distal end become more like hooks. Marginal and submarginal lamellae are found, and James's flamingo has the greatest number of both, which also means a smaller intermarginal distance is seen between them. About 21 lamellae per cm are found in this species, which is more than twice the number found in other flamingos.
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The nostril, orbit and tympanic membrane are all directed upward, but whether the eye could be projected upward above the head to give a horizontal view, similar to a frog, is difficult to determine. The first rib is short, but the second, which is in undisturbed position, implies a body width of at least 35 cm. The shoulder girdle is a rigid structure, the membrane bones lying in the skin having a maximum width of 44 cm at a point a little behind the lower jaws. The clavicles are upturned so that they incline inward, and have a minimum width of 23 cm.
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Mitteilungen as dem Museum für Naturkunde, Berlin, Geowissenschaftliche Reihe 4: 189–222 In 2013, Taissa Rodrigues and Alexander Wilhelm Armin Kellner concluded that Lonchodectes sagittirostris lacked any distinguishing traits and was therefore a nomen dubium. In 2017, Stanislas Rigal, David Martill and Steven Sweetman disagreed with this and named a separate genus Serradraco, resulting in the new combination Serradraco sagittirostris. The type species of the genus is the original Pterodactylus sagittirostris. The generic name is a combination of the Latin serra, "saw" and draco, "dragon", referring to the saw-like upper profile of the lower jaws.
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Map of the type locality of Liaodactylus, with its position in the stratigraphic column There is one specimen of Liaodactylus known, namely the holotype PMOL-AP00031, which is stored at the Palaeontological Museum of Liaoning. It consists of a complete skull and lower jaws, along with the first two cervical vertebrae. It originates from outcrops located about west of the village of Daxishan, in Jianchang County, Liaoning, China. These outcrops belong to the Late Jurassic Tiaojishan Formation, which has been dated to range from 161.8 ± 0.4 to 159.5 ± 0.6 million years ago (Oxfordian) based on argon-argon dating.
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Zygophyseter varolai is an extinct sperm whale that lived during the Tortonian age of the Late Miocene 11.2 to 7.6 million years ago. It is known from a single specimen from the Pietra Leccese Formation in Italy. It was a member of a stem group of fossil macroraptorial sperm whales (often shortened to "raptorial") also including Brygmophyseter, Acrophyseter, and Livyatan. It probably grew to be around in length and shared some characteristics with other raptorials, such as large teeth with tooth enamel that were functional in both the upper and lower jaws which the modern sperm whale (Physeter macrocephalus) lacks.
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Tembeassu marauna is a species of weakly electric knifefish in the family Apteronotidae and the only member of its genus, known only from three specimens collected from the upper Paraná River, Brazil, in 1965. This fish can be identified by fleshy extensions at the tips of its upper and lower jaws, with the upper extension bearing a patch of extra teeth. The function of these unique structures is unknown, but may relate to feeding. Apparently a specialized inhabitant of deep riverine environments, T. marauna may be endangered by extensive dam construction in the upper Paraná region, if not already extinct.
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In the morning hours of 14 July 2019 on the Banja Luka-Prijedor state road near the village of Ramići, Kuzmić was involved in a serious traffic accident. Driving his Porsche SUV, the twenty-nine-year-old professional basketball player reportedly collided with a BMW vehicle going in the opposite direction while traveling at a high rate of speed. He sustained life-threatening injuries in the accident, breaking his maxilla and mandible head bones (upper and lower jaws), as well as his chest. He was immediately placed in induced coma and airlifted via helicopter to the Clinical Centre of Serbia in Belgrade.
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Relative to body size, Gorgonops had a deep skull which had a triangular profile when viewed from above. Perhaps the most distinctive features were two enlarged canine teeth that were so big (12-cm long) they almost protruded beyond the lower jaw. To help protect these teeth, the lower jaws grew in such a shape so that the anterior (front) portion was thicker than the posterior (rear) portion. This form would have protected the enlarged canine teeth from accidental damage, and was similar in bone function to the flanges of bone of sabre-toothed cats in the Cenozoic.
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Another stem tetrapod, Sigournea multidentata from the Early Carboniferous of the United States, may also be related to Spathicephalus. Named in 2006 from a Visean-aged fissure fill deposit in Iowa, Sigournea is slightly older than Spathicephalus. It resembles both Spathicephalus and Doragnathus in having numerous small, closely packed teeth. Sigournea differs from Spathicephalus and resembles Doragnathus in having pointed rather than chizel-shaped marginal teeth and a second row of teeth in the lower jaws, and differs from both taxa in having a hole on the inner surface of the lower jaw called the exomeckelian fenestra.
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Euromycter is an extinct genus of medium-sized caseid synapsids from Early (Artinskian-Kungurian) or Middle (Roadian-Wordian) Permian deposits of Southern France. The holotype and only known specimen of Euromycter (MNHN.F.MCL-2) includes the complete skull with lower jaws and hyoid apparatus, six cervical vertebrae with proatlas, anterior part of interclavicle, partial right clavicle, right posterior coracoid, distal head of right humerus, left and right radius, left and right ulna, and complete left manus. It was collected by D. Sigogneau-Russell and D. Russell in 1970 at the top of the M1 Member, Grès Rouge Group, near the village of Valady (département of Aveyron), Rodez Basin.
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The lower jaw of Ufudocyclops is only partially known, and is only known from one of the referred specimens. Most of what is preserved consists of the front half of the mandibles, namely the two dentaries, as well as a splenial and portions of the angulars. The jaws are also missing the tip of the mandibular symphysis at the very front where the two jaw bones are fused, but enough is preserved to suggest the lower beak was somewhat squared off. The dentaries are toothless and covered in pits and grooves like those of the upper jaws, typical of the beaked lower jaws of derived dicynodonts.
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Additionally, he noted the presence of what he interpreted as the remnants of a dermal structure surrounding the beak. Significantly, Cope regarded his Diclonius as an amphibious animal consuming soft water vegetation. His reasoning was that the teeth of the lower jaw were weakly connected to the bone and liable to break off if used to consume terrestrial food, and he described the beak as weak as well. Unfortunately for Cope, aside from misidentifying several of the bones of the skull, by chance the lower jaws he was studying were missing the walls supporting the teeth from the inside; the teeth were actually well- supported.
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This is the original skeleton found by Mertens. Specimen PMU 24705 consists of a partial skeleton with skull and lower jaws comprising these bones: the rostral part of the left nasal; a partial right jugal; the tapered jugal process of the postorbital, partially excavated; the dorsal process of the right quadratojugal; the fragmented left pterygoid (another fragment might be the right splenial, but it is too fragile to be removed from its matrix), a series of twenty-five presacral vertebrae and the left thighbone. The second skeleton, of an individual about as large as the holotype, was designated "Exemplar b" by Wiman. It was by Wilson & Upchurch referred to Euhelopus.
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Plesiosaur skeleton of Meyerasaurus in the Museum am Löwentor, Stuttgart, seen from below In general, plesiosaurians varied in adult length from between to about . The group thus contained some of the largest marine apex predators in the fossil record, roughly equalling the longest ichthyosaurs, mosasaurids, sharks and toothed whales in size. Some plesiosaurian remains, such as a long set of highly reconstructed and fragmentary lower jaws preserved in the Oxford University Museum and referable to Pliosaurus rossicus (previously referred to Stretosaurus and Liopleurodon), indicated a length of . However, it was recently argued that its size cannot be currently determined due to their being poorly reconstructed.
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Life restoration of Bellubrunnus showing forward-curving wingtips The holotype specimen of Bellubrunnus represents a small individual, with a wingspan of less than a foot, and is one of the smallest pterosaur fossils known. Nearly every bone is preserved in BSP–1993–XVIII–2, although no soft tissues have been found, neither as impressions nor as organic remains. The entire skeleton is complete except for missing parts of the right foot and tail tip. Because the skeleton is preserved in ventral view, many details of the skull ("sk" in the skeletal diagram) are obscured by the lower jaws (dentary, "dt" + angular, "ar" in the skull diagram).
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While most famous forms such as Gomphotherium had long lower jaws with tusks, which is the ancestral condition for the group, after these forms became extinct, the surviving gomphotheres had short jaws with either vestigal or no lower tusks (brevirostrine), looking very similar to modern elephants, an example of parallel evolution. Beginning after 2 Mya, they were gradually replaced by mammoths and mastodons in most of North America, with the last two genera, Cuvieronius persisting in southern North America and Notiomastodon having a wide range over most of South America, until the end of the Pleistocene. The name "gomphothere" comes from Ancient Greek (), "peg, pin; wedge; joint" plus (), "beast".
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Reconstructed skeleton in side view Brygmophyseter is a member of a fossil stem group of hyper-predatory macroraptorial sperm whales from the Miocene (often shortened to "raptorial") The other members are Acrophyseter, Livyatan, and Zygophyseter, and these four whales have in common enamel-coated teeth in both the upper and lower jaws which were used in hunting large prey. These teeth are thought to have evolved in either a basilosaurid-like common ancestor, or multiple times independently in the group. Brygmophyseter is the oldest raptorial. It has been proposed that these raptorials be placed into the extinct paraphyletic (hence, probably invalid) subfamily Hoplocetinae, alongside Scaldicetus, Diaphorocetus, Idiorophus, and Hoplocetus.
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It consists of two upper jawbones, left and right maxillae. Maleev erroneously assumed these represented the lower jaws. Referred was specimen PIN 554/2-1, the rear of the skull of another individual. In 1977, Teresa Maryańska noted a similarity with another Mongolian ankylosaur, Talarurus, in that both taxa have separate openings for the ninth to twelfth cerebral nerve; she therefore renamed the species as Talarurus disparoserratus.T. Maryańska, 1977, "Ankylosauridae (Dinosauria) from Mongolia", Palaeontologia Polonica 37: 85-151 Having determined that Syrmosaurus is a junior synonym of Pinacosaurus, Soviet palaeontologist Tatyana Tumanova named the material as a new genus Maleevus in honor of Maleev in 1987.
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The bones looked similar facially to those of humans today but had much larger lower jaws and elongated braincases. They have similar features to the Florisbad Skull dating to 260,000 years ago found at the other end of the continent, in Florisbad, South Africa, which has been attributed to Homo sapiens on the basis of the Jebel Irhoud finds. Jean-Jacques Hublin at Jebel Irhoud (Morocco), pointing to the crushed human skull (Irhoud 10) whose orbits are visible just beyond his finger tip. The tools were found alongside gazelle bones and lumps of charcoal, indicating the presence of fire and probably of cooking in the cave.
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Bergisuchus is only represented by the holotype snout and lower jaw (HLMD-Me 7003) and the referred pair of lower jaws (GM XVIII-49), so much of its anatomy is unknown. The snout is tall and laterally compressed, unlike the broad flat snouts of modern crocodylians, with tall nasals that form a raised, sharp midline along the length of the snout. Rossmann and colleagues reconstructed the incomplete premaxillae as tall and steep based on the dimensions of the maxilla, more similar in shape to those of Baurusuchus, Barinasuchus and Bretesuchus than to Sebecus. The premaxilla may also have sloped downwards, similar to that of Bretesuchus.
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Squalus is a genus of dogfish sharks in the family Squalidae. Commonly known as spurdogs, these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower jaws similar in size, caudal peduncle with lateral keels; upper precaudal pit usually present, and caudal fin without subterminal notch. In spurdogs, the hyomandibula (the bone connecting the braincase to the jaws) is oriented at a right angle to the neurocranium, while in other sharks, the hyomandibula runs more parallel to the body. This led some to think that the upper jaw of Squalus would not be as protractile as the jaws of other sharks.
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Because it survived the attack, Carpenter suggested that it may have outmaneuvered or outrun its attacker, or that the damage to its tail was incurred by the hadrosaurid using it as a weapon against the tyrannosaur. [not printed until 2000] Another specimen of E. annectens, pertaining to a long individual from South Dakota, shows evidence of tooth marks from small theropods on its lower jaws. Some of the marks are partially healed. Michael Triebold, informally reporting on the specimen, suggested a scenario where small theropods attacked the throat of the edmontosaur; the animal survived the initial attack but succumbed to its injuries shortly thereafter.
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Ultimately five nearly complete skeletons, more than 100 skulls, and forty-eight lower jaws as well as numerous isolated bones were found. Some paleontologists believed that such a large amount of fossils found in one location was because of the quarry area being a watering hole at one point. The waterhole could have been where the bones of the Hagerman horses accumulated as injured, old, and ill animals, drawn to water, died there. Other paleontologists think that an entire herd of these animals drowned attempting to ford a flooded river and were swept away in the current and ended up buried in the soft sand at the bottom.
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Each nostril is split into tiny incurrent and excurrent openings by a flap of skin in front; the flap has a three-lobed shape with the central lobe forming a long, conical barbel. The barbels are thicker than in the leopard catshark, and do not reach the mouth. The eyes are horizontally oval and placed rather high on the head, with rudimentary nictitating membranes (protective third eyelids) and a thick ridge running underneath. The sizable mouth forms a broad arch, with short furrows extending from the corners onto both the upper and lower jaws; the upper teeth are exposed when the mouth is closed.
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Parasuminia is only known from incomplete remains of the lower jaw and the front of the snout. Compared to Suminia, the lower jaw is deeper and more robust, and is down-turned towards its tip with a deep, rounded 'chin'. The teeth in both the upper and lower jaws are lower and wider than in Suminia, with serrated edges only found on the newest replacement teeth before being worn away. The tooth row consists of 10 to 12 teeth and is straight along its surface, with longer procumbent (forward projecting) incisors at the tip of the lower jaw to accommodate the down-turned tip.
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The fossil of Docofossor brachydactylus, holotype BMNH 131735, along with that of Agilodocodon scansorius, was originally found by farmers near Nanshimen in the province of Hebei in a layer of the Chinese Tiaojishan Formation (Oxfordian) and acquired by the Beijing Museum of Natural History. The holotype consists of a compressed skeleton with skull and lower jaws, preserved on a plate and counterplate, along with soft-tissue remnants. The shoulder girdle area and the tail have been damaged. The type species Docofossor brachydactylus was named and described by Zhe-Xi Luo, Meng Qingjin, Ji Qiang, Liu Di, Zhang Yuguang, and April I. Neander in the journal Science in 2015.
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The teeth of both the upper and lower jaws are small and cone-shaped, some having slightly serrated edges, and are only differentiated by slight differences in length (some other synapsids have teeth that vary greatly and shape across their jaws). The three forward- most dentary teeth are angled slightly outward as in more derived synapsids such as Dimetrodon and Sphenacodon. Several features, including straight- margined maxillae and simple conical teeth, are also seen in the earliest reptiles. Twenty-three presacral (neck and back) vertebrae are preserved in the holotype, although several may be missing because the typical number of presacral vertebrae in early synapsids is 27.
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The two most anterior of these arches are thought to have become the jaw itself (see hyomandibula) and the hyoid arch, which braces the jaw against the braincase and increases mechanical efficiency. While there is no fossil evidence directly to support this theory, it makes sense in light of the numbers of pharyngeal arches that are visible in extant jawed (the Gnathostomes), which have seven arches, and primitive jawless vertebrates (the Agnatha), which have nine. Meckel's cartilage is a piece of cartilage from which the mandibles (lower jaws) of vertebrates evolved. Originally it was the lower of two cartilages which supported the first gill arch (nearest the front) in early fish.
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The only known skull of Feeserpeton is small, but well-fused bones, deep pitting, and worn teeth indicate that the individual was close to maturity when it died. Large eye sockets may indicate that Feeserpeton was nocturnal. The skull is nearly complete, missing parts of the premaxilla (a bone at the tip of the snout) and the jugal (a bone making up the "cheek" region). A combination of features distinguish Feeserpeton from other related parareptiles, including a triangular skull, large caniniform teeth in the upper and lower jaws, and postorbital bones behind the eye sockets that are much larger than the nearby squamosal bones.
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To complete the mount, sauropod feet that were discovered at the same quarry and a tail fashioned to appear as Marsh believed it shouldbut which had too few vertebraewere added. In addition, a sculpted model of what the museum thought the skull of this massive creature might look like was made. This was not a delicate skull like that of Diplodocuswhich was later found to be more accuratebut was based on "the biggest, thickest, strongest skull bones, lower jaws and tooth crowns from three different quarries". These skulls were likely those of Camarasaurus, the only other sauropod for which good skull material was known at the time.
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The first fingers were large, being both longer and thicker than either of the bones of the forearm. The teeth differed slightly (they were heterodont) based on position: those near the tips of the upper jaws (on the premaxillae) were slender and lacked serrations, while those behind them (on the maxillae) were serrated and laterally compressed. The teeth of the lower jaws were similarly differentiated. A pigmented area in the abdomen of the holotype has been suggested as possible traces of organs, and was interpreted as the liver by John Ruben and colleagues, which they described as part of a crocodilian-like "hepatic piston" respiratory system.
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Eohyosaurus is known solely from the holotype SAM-PK-K10159, a partial skull missing the front end, with associated incomplete lower jaws currently housed at the Iziko South African Museum, Cape Town. The specimen was discovered by Frederik Petrus Wolvaardt in December 2000, loose on boulder-strewn slopes at the base of a cliff, at Farm Lemoenfontein 44, Rouxville District of the Free State Province. It was collected from the middle deposits of the Burgersdorp Formation of Beaufort Group. This horizon belongs to Subzone B of the Cynognathus Assemblage Zone, dating to the early Anisian stage of the early Middle Triassic period, about 246 million years ago.
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Fraas, E., 1913, "Die neuesten Dinosaurierfunde in der schwäbischen Trias", Naturwissenschaften 1(45): 1097-1100 The type specimen is housed in the collection of the State Museum of Natural History in Stuttgart, Germany. In 1921, Friedrich von Huene referred two more specimens, both also found in the Burrer quarry, in 1908, to Procompsognathus: SMNS 12352, a partial skull and lower jaws from a larger individual than the holotype, and SMNS 12352a, an isolated left hand.Von Huene, F., 1921, "Neue Pseudosuchier und Coelurosaurier aus dem württembergischen Keuper", Acta Zoologica 2: 329-403 The genus name Procompsognathus, means "before elegant jaw", and is derived from the name of another dinosaur, Compsognathus.
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Although the forelimbs are not completely known, they were very short, while the hind limbs were longer and very stocky. It can be distinguished from other abelisaurids by its wider skull, the very rough texture and thickened bone on the top of its snout, and the single rounded horn on the roof of its skull, which was originally mistaken for the dome of a pachycephalosaur. It also had more teeth in both upper and lower jaws than most abelisaurids. Known from several well-preserved skulls and abundant skeletal material, Majungasaurus has recently become one of the best-studied theropod dinosaurs from the Southern Hemisphere.
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London: Salamander Books Ltd as it explains the unusual wear patterns of the teeth (coming from tooth–food contact). In unilateral branch stripping, one tooth row would have been used to strip foliage from the stem, while the other would act as a guide and stabilizer. With the elongated preorbital (in front of the eyes) region of the skull, longer portions of stems could be stripped in a single action. Also, the palinal (backwards) motion of the lower jaws could have contributed two significant roles to feeding behaviour: 1) an increased gape, and 2) allowed fine adjustments of the relative positions of the tooth rows, creating a smooth stripping action.
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Huanansaurus was one of eighteen dinosaur taxa from 2015 to be described in open access or free-to-read journals. The holotype, HGM41HIII-0443, was found in a layer of the Nanxiong Formation dating from the Campanian - Maastrichtian. It consists of a partially articulated, incomplete skeleton which includes a nearly complete skull and lower jaws, the first seven neck vertebrae, a humerus, ulna, radius and hand of the right arm, the left hand, the lower part of the right thighbone, the upper part of the right shinbone, and the distal parts of the right foot. The specimen is part of the collection of the Henan Geological Museum at Zhengzhou.
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Based on the closer packing and smaller size of the dentary teeth compared to those in the corresponding length of the premaxilla, the difference between the number of teeth in the upper and lower jaws appears to have been more pronounced than in other theropods. The terminal rosette in the upper jaw of the holotype had thirteen (tooth sockets), six on the left and seven on the right side, showing tooth count asymmetry. The first four upper teeth were large (with the second and third the largest), while the fourth and fifth progressively decreased in size. The diameter of the largest was twice that of the smallest.
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Chaoyangopterus is based on holotype IVPP V13397, which includes the front of the skull, the lower jaws, the neck vertebrae, the shoulder and pelvic girdles, and the limbs. The skull is about 270 millimeters long (10.6 inches) and toothless, and its wingspan is estimated to have been around 1.85 meters (6.07 feet). Wang and Zhou concluded that it compared most closely to Nyctosaurus and classified it as a nyctosaurid, although they found that its shin was proportionally longer compared to the femur and humerus in Chaoyangopterus, that their animal had relatively shorter wings and longer legs than Nyctosaurus, and that it still had four fingers.
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The jaws and neck of Boii illustrated by Frič (1883) from impressions The crushed skull was pressed between two plates of coal which preserved the outer impressions of bones on both the underside and upper side of the specimen. Although not all of the bones were preserved, the outer impressions helped to reconstruct the structure of these missing bones. The impressions were used to reconstruct the skull and lower jaws, while the skull itself (which preserved the palate better than the impressions) was removed and encased in Canada balsam. The skull was initially believed to have been stout, approximately as long as it was wide.
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Having a close European relative of the American form Dryosaurus named led to most of the dryosaurid fossil material of Europe being referred to Valdosaurus. Valdosaurus was seen as not only present in England (the Wessex Formation of the Isle of Wight and the Hastings Beds of West Sussex) but also in Romania (the Cornet Bauxite of Bihor; this species is sometimes referred to as the separate species "Bihariosaurus") and Spain. These rock units were deposited between the Berriasian and Barremian stages, between approximately 145 and 125 million years ago. V. canaliculatus would then be known from thigh bones, extensive additional postcranial elements, partial lower jaws, and teeth.
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Lower jaws at various growth stages It was identified that Europasaurus was a unique dwarf species, and not a juvenile of an existing taxon like Camarasaurus, by a histology analysis of multiple specimens of Europasaurus. The youngest specimen (DFMMh/FV 009) was shown by this analysis to lack signs of aging such as growth marks or laminar bone tissue, and is also the smallest specimen at in length. Such bone tissue is an indicator of rapid growth, so the specimen is probably a young juvenile. A larger specimen (DFMMh/FV 291.9) at shows large amounts of laminar tissue, with no growth marks present, so is likely a juvenile as well.
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The age of the layer was determined at 75.97 million years by zircon dating. The holotype consists of a partial skeleton with skull. It contains the complete skull and lower jaws, including the predentary; four back vertebrae; eight sacral vertebrae; eight "free" tail vertebrae; eleven tail vertebrae forming the handle of the tail club; the tail club itself; ribs; both shoulder blades; a left coracoid; a right humerus; a right ulna; a left ilium; a left thighbone; a left shinbone; a left calfbone; a toe phalanx; a claw; two cervical halfrings; and fourteen osteoderms of the back and flanks. It represents about 45% of the skeletal elements.
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The holotype, IVPP V15709, consists of a skull, the lower jaws, a neck vertebra, a dorsal vertebra, three tail vertebrae, the left ulna and hand, the lower ends of both pubes and both lower legs. Some estimates suggest that Aorun was at best 1 m (3.3 ft) long and weighed 2 kilograms (4.4 lbs) at most. In the skull, the right orbit contains a nearly complete sclerotic ring which is composed of overlapping ossicles. The gracile hand of this specimen, which has particularly thin metacarpals III and IV more closely approximates the hands of derived non- avian coelurosaurs (Gishlick & Gauthier 2007) than the hands of more basal theropods.
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However, no lemuriform toothcomb has been found in the fossil record of the Eocene, and the European adapid lower jaws from that time did not resemble the derived state seen in lemuriforms. Lemuriforms are currently thought to have evolved in Africa, and the earliest known strepsirrhine primates from Africa are azibiids from the early Eocene, which likely descended from a very early colonization of the Afro-Arabian land mass in the Paleocene (66 to 55 mya). Stem lemuriforms, including Djebelemur and 'Anchomomys' milleri, have been found in Africa and date from 50 to 48 mya and were very distinct from European adapiforms. However, they lack a toothcomb.
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The wingspan of Feilongus was estimated by Wang and colleagues to have been around 2.4 meters (7.9 feet), making it large for a basal pterodactyloid. Feilongus is notable for having two bony crests on the skull (one long and low on middle of the snout, and one projecting backwards from the rear of the skull), and for the upper jaws being 10% or 27 millimetres longer than the lower jaws, giving it a pronounced overbite. The second specimen however, shows neither crests nor overbite. The preserved part of the second crest was short with the leading edge rounded, and may have had a nonbony extension, now lost.
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From this Head estimated the length of the type specimen of Protohadros at seven to eight metres. He pointed out that this specimen was that of a subadult and that fully-grown individuals could have been longer. Protohadros had a massive, very deep set of lower jaws, and the snout was strongly turned down at the front, which according to Head suggested a habit of grazing on low-growing plants, rather than browsing from bushes or overhanging branches. Its diet would then have consisted of the swamp plants which grew in the delta streams in its habitat, scooped up by the broad, down-turned mouth.
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The Malabar snakehead differs from all other species in the genus by its high number of lateral line scales (103–105 vs. 36–91). It further differs from all other Channa species, except C. bankanensis, C. lucius, C. micropeltes and C. pleurophthalma, by the presence of gular scales, a patch of scales between the anterior tips of the lower jaws, visible in ventral view. C. diplogramma differs from C. bankanensis, C. lucius, and C. pleurophtalma by having a very different color pattern, and from its sister species C. micropeltes by a combination of characteristics, viz. number of caudal fin rays, lateral line scales, scales below lateral line; total vertebrae, pre-anal length, and body depth.
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The holotype specimen, LH 7777, part of the Las Hoyas Collection presently housed at the Museo de Cuenca, Cuenca, Spain, of Pelecanimimus was recovered at the La Hoyas locality in Cuenca Province, Spain, from lagerstätte beds within the Calizas de La Huérguina Formation dating to the Lower Barremian. The only known specimen consists of the articulated front half of a skeleton and includes the skull, lower jaws, all the neck vertebrae and most of the back vertebrae, ribs, sternum, the pectoral girdle, a complete right forelimb and most of the left forelimb. Remains of the soft parts are visible at the back of the skull, around the neck and around the front limbs.
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Huanhepterus had a long, low skull, with a low crest running along the midline that was higher toward the tip of the snout and became smaller toward the eyes. The teeth, about 26 pairs in the upper and 25 in the lower jaws, were slender and numerous, and became shorter farther from the 11th pair, both to the front as to the back, where they become absent completely in posterior part of the snout. The cervical vertebrae were long, as were the toes, and there was no fused complex of the front dorsal vertebrae (notarium), as seen in other pterosaurs. The wingspan of the type individual was estimated at 2.5 m (8.2 ft).
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The holotype, AODF 876, was found in a layer of the Winton Formation dating from the Cenomanian - lower Turonian, about ninety-six million years old. It consists of a partial skeleton with skull and lower jaws. It contains the front part of the head with the premaxillae, the maxillae and the dentaries; the left frontal bone, the rear part of the left lower jaw; forty single teeth; five neck vertebrae; the right shoulder joint; the left ulna; the left radius; the proximal and distal left wrist bones; two fourth metacarpals; phalanges from the first to third fingers of the left hand; and the first phalanx of the fourth finger. It represents a fully-grown but not yet mature animal.
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Lonchognathosaurus is based on holotype SGP 2001/19, found near Urumqi in the southern Junggar Basin, the front portion of a skull and lower jaws that came from a large individual; the estimated length of the complete skull was about 400 mm (15.75 in). The point of the upper jaw, composed of the premaxilla bones, was slender and had a needle-like tip. The teeth of the upper jaw appeared far back of the tip, and were well-spaced, diminishing in size from front to back; they ended again in front of the nostrils. They were placed in tooth-sockets that had a low bony ridge but were not otherwise elevated from the jaw.
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It is believed that pits represent vestigial dental alveoli that once held an additional pair of teeth in ancestral species but devolved in Megacephalosaurus. Almost all pliosaurs normally have five pairs of premaxillary teeth and this feature of reduction to four pairs is fairly unique among pliosaurs; it has only been documented elsewhere in Kronosaurus, Brachauchenius and Acostasaurus, indicating that the reduction to four pairs of premaxillary teeth may have been a novel adaptation introduced by Cretaceous pliosaurs. The lower jaws bear twenty-three pairs of functional teeth. Only the five frontmost pairs are relatively large, all teeth subsequent of them get progressively smaller as they progress towards the base of the dentary in a smooth transition.
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In 1999, Rosendo Pascual and colleagues described a lower jaw of Sudamerica, which had previously only been known from isolated teeth. This jaw fragment showed that Sudamerica had four molariform teeth on each side of the lower jaws, more than any multituberculate, and consequently they removed gondwanatheres from Multituberculata and regarded their affinities as uncertain. As a consequence, Kielan-Jaworowska and colleagues excluded Gondwanatheria from multituberculates, but identified the jaw fragment and a few upper premolars of Ferugliotherium as indeterminate multituberculates in a 2001 paper and a 2004 book. However, in 2009 Yamila Gurovich and Robin Beck identified these fossils as Ferugliotherium and argued in favor of a close relationship between gondwanatheres (including Ferugliotheriidae) and multituberculates.
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Orthognathic surgery, also known as corrective jaw surgery, is performed to normalise dentofacial deformity and reposition part/all of the upper and/or lower jaws to improve occlusion stability and facial proportions. It is the 'mainstay treatment for patients who are too old for growth modification and for dentofacial conditions that are too severe for either surgical or orthodontic camouflage.' The surgery usually involves gaining access to the bone from inside the mouth, revealing and moving the bone into a correct functional position, and fixing it in position with metal plates and screws. These plates are most often left in the bone, but at times require removal due to infection, which would require another operation.
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Protoceratopsids may have had cheeks to hold food in their mouths. They have very well-defined maxillary and dentary ridges where the muscles in the cheek would have connected, and a number of foramina dotted the maxilla which allowed branches from the trigimenal nerve to reach the tissues attached to the maxilla, indicating that such tissues were likely muscular. The end of the upper jaw was likely not fleshy but instead covered by a horn-like material, and the upper and lower jaws curved in towards each other. Compared to more derived ceratopsians, protoceratopsids had a deep and wide oral cavity, though more narrow than in predecessors like Psittacosaurus, which may have aided in breathing or thermoregulation.
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Hongshanornis longicresta was a small species, especially compared to other early ornithuromorphs (birds with a modern tail anatomy), about the size of a thrush, and adult specimens are estimated to have weighed about in life, with a wingspan of about . Interpretive drawing of specimen DNHM D2946, showing location of gizzard stones The skull in all known specimens is poorly preserved, but in general appears to have had a narrow snout compared to the closely related Longicrusavis. The teeth were very small and are poorly preserved in all known specimens. At first, this led scientists to conclude that the teeth were absent in both the upper and lower jaws, probably replaced with a beak.
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Plesiosaur skeleton of Meyerasaurus in the Museum am Löwentor, Stuttgart, seen from below In general, plesiosaurians varied in adult length from between to about . The group thus contained some of the largest marine apex predators in the fossil record, roughly equalling the longest ichthyosaurs, mosasaurids, sharks and toothed whales in size. Some plesiosaurian remains, such as a long set of highly reconstructed and fragmentary lower jaws preserved in the Oxford University Museum and referable to Pliosaurus rossicus (previously referred to Stretosaurus and Liopleurodon), indicated a length of . However, it was recently argued that its size cannot be currently determined due to their being poorly reconstructed and a length of metres is more likely.
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They are positioned closer to the midlines of the upper and lower jaws than are the incisors due to an inward expansion of the maxilla and dentary bones. Microgomphodon is very similar in appearance to Bauria, but differs in having a small hole called a pineal foramen at the top of the skull behind the eye sockets, a complete postorbital bar enclosing the eye sockets from behind, fewer postcanine teeth, and canines located farther back along the upper jaw. Additionally, the two taxa can be distinguished by many subtle differences relating to the shape of the skull. For example, Microgomphodon has a deeper snout, slightly larger eyes, and a sharper angle to the zygomatic arches than does Bauria.
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Like other typical gomphotheres, Amebelodon possessed two sets of tusks, one upper set, (much like those found on modern elephants), and one lower set that extended from the very front of the lower jaws. However, as mentioned above, the lower tusks of the Amebelodon were distinctive in that they were relatively long, slender, and flattened. Because of the resemblance of these lower tusks to shovels, Amebelodon is commonly referred to as a "shovel-tusked" gomphothere (another shovel-tusked gomphothere that may or may not be closely related to Amebelodon is Platybelodon). There has long been an assumption that these lower tusks were actually used as shovels by the animal during feeding, presumably to dig up water plants.
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The hadrosaurs and ceratopsians of the Cretaceous Period, as well as many herbivorous mammals, would convergently evolve somewhat analogous dental batteries. As opposed to hadrosaurs, which had hundreds of teeth constantly being replaced, tooth replacement in heterodontosaurids occurred far more slowly and several specimens have been found without a single replacement tooth in waiting. Characteristically, heterodontosaurids lacked the small openings (foramina) on the inside of the jaw bones which are thought to have aided in tooth development in most other ornithischians. Heterodontosaurids also boasted a unique spheroidal joint between the dentaries and the predentary, allowing the lower jaws to rotate outwards as the mouth was closed, grinding the cheek teeth against each other.
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The holotype, MMS/VBN.09.C.001, was discovered in a sandstone layer of the Aix-en- Provence basin, dating from the late Campanian, about seventy-two million years old. It consists of a partial skeleton with skull. It contains the symphysis of the lower jaws, the atlas-axis complex of the front neck, a middle neck vertebra, the left humerus, a piece of the right humerus, the left radius, the right pteroid, the shaft of the fourth metacarpal, the proximal part of the first phalanx of the wing finger, the distal part of the same phalanx, and four bone fragments that could not be identified including some articular surface and two shafts.
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Skull diagram of Azendohsaurus madagaskarensis The skull of A. madagaskarensis is almost completely known, and is robustly built with a short and boxy shape and a deep snout. The premaxillae are gently curved at the front of the upper jaw, forming a blunt, round snout tip, while the lower jaws have a deep, down- turned tip like those of sauropods. The bony nostrils are fused into a single (confluent) opening that faces forwards at the front of the snout, similar to those of rhynchosaurs. The skull has a number of traits convergent with sauropodomorphs, including the downward curving dentary, a robust dorsal process of the maxilla, and several features of the teeth.
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Excavation of the holotype specimen The first fossil remains of Styracosaurus were collected in Alberta, Canada by C.M. Sternberg (from an area now known as Dinosaur Provincial Park, in a formation now called the Dinosaur Park Formation) and named by Lawrence Lambe in 1913. This quarry was revisited in 1935 by a Royal Ontario Museum crew who found the missing lower jaws and most of the skeleton. These fossils indicate that S. albertensis was around 5.5 to 5.8 meters in length and stood about 1.65 meters high at the hips. An unusual feature of this first skull is that the smallest frill spike on the left side is partially overlapped at its base by the next spike.
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In a 2017 study of niche partitioning in therizinosaurs through digital simulations, Lautenschlager found the dentaries of Segnosaurus experienced one of the lowest stress magnitudes during extrinsic feeding scenarios. Segnosaurus and Erlikosaurus were aided by the down-turned tip of the lower jaws and symphyseal regions, and probably also by beaks, which are known to mitigate stress and strain. By contrast, the straighter and more elongated dentaries of basal therizinosaurs—typical of their coelurosaurian ancestors—had the highest magnitudes of stress and strain. A downwards-pulling motion of the head while gripping vegetation was more likely than a sideways or upwards movement, though such behavior would be more likely in Segnosaurus and Erlikosaurus with their stress-mitigating jaws.
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Some observations categorize the difference between this species and other members of its family is the absence of said fin, whilst others claim that it does have the anal fin and that it leads to the caudal fin. The name ‘Rabbit Fish’ originates from its large tooth-plates within its upper and lower jaws, giving it a rabbit like appearance. This family is also often referred to as “Rat Fish” as well due to its long tapered tail . The combination of these parts resembling a variety of animals is what gave its family the name Chimaera - representing the creature by the same name in Greek mythology that combined a multitude of beasts.
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A study by Susannah Maidment e.a. concluded that juvenile specimens show that this bone was a fusion of three elements, one in front, the next in rear, and the third at the inner side.Maidment, S.C.R., Porro, L.B., 2010, "Homology of the palpebral and origin of the supraorbital ossifications in ornithischian dinosaurs", Lethaia, 43: 95-111 The premaxilla, the bone forming the snout tip, was short and no predentary, the bone core of the lower beak on the tip of the stout lower jaws, has been found, so the horny beak that is assumed present with all ornithischians was likely very short. Its teeth were longer and more triangular in side view than in later armoured dinosaurs.
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The holotype MSNTUP I-15459 of Aegyptocetus tarfa Aegyptocetus is known from the articulated holotype MSNTUP I-15459, an almost complete cranium, lower jaws (with teeth) and a partial postcranial skeleton (cervical and thoracic vertebrae and ribs). The specimen was recovered when marbleized limestone was imported commercially to Italy. It was collected in the Khashm el-Raqaba limestone quarry (, paleocoordinates ) from the Gebel Hof Formation on the northern flank of Wadi Tarfa in the Eastern Desert of Egypt, dating to the late Mokattamian age of the middle Eocene, about . Its cause of death may have been an attack by a large shark as pattern of shark tooth marks preserved on the ribs.
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Brygmophyseter skeleton The macroraptorial sperm whales are a paraphyletic fossil group of hyper-predatory stem sperm whales comprising four genera: Acrophyseter, Brygmophyseter, Livyatan, and Zygophyseter. These macroraptorials all share large, functional, enamel-coated teeth on both the upper and lower jaws, which were used in capturing large prey. In contrast, the modern sperm whale (Physeter macrocephalus) lacks enamel, teeth in the upper jaw, and the ability to use its teeth to catch prey. However, Livyatan belongs to a different lineage than the other macroraptorials, and the development of large size and the spermaceti organ, an organ that is characteristic of sperm whales, are thought to have evolved independently from the other macroraptorials.
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Proburnetia, a biarmosuchian with strange bumps and bosses on its skull, from the Late Permian of Russia The biarmosuchian skull is very similar to the sphenacodontid skull, differing only in the larger temporal fenestra (although these are still small relative to later therapsids), slightly backward-sloping occiput (the reverse of the pelycosaur condition), reduced number of teeth, and single large canine teeth in both upper and lower jaws, and other features (Carroll 1988 pp. 370, Benton 2000 p. 114). In later specialised Biarmosuchia, these resemble the enlarged canines of the Gorgonopsia. The presence of larger jaw-closing muscles (and hence a stronger bite) is indicated by the flaring of the rear of the skull where these muscles were attached.
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Each of the dentary bones is very slender, only about 22 mm wide even at the slightly thickened 'chin' of the symphysis. While L. thaumastos has a small crest running along the lingual side of the dentary to thicken it, this feature is not present in L. maghrebensis. The splenial is a very thin sheet of bone in both species; it stretches much of the way along the lower jaws, but does not participate in the symphysis as the dentary does. The anterior end of the splenial differs between the two species; in L. thaumastos it is bifurcated, whereas in L. maghrebensis the anterior end of the splenial comes to a simple point.
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Restoration of Metriorhynchus, of which remains have been found alongside Wiehenvenator After discovering the initial remains of Wiehenvenator, members of the excavation team returned to the site and continued to search the surroundings for further material. After searching 35m both east and west of the Ornatenton Formation, some weathered vertebral centra and teeth of Liopleurodon were found. One year later, in mid-October 1999, the remains consisting of a maxillary fragment, bone fragments, and a tooth, of a second theropod were found 28.5 m north-west of the first locality. On October 3, 2014, in an overgrown quarry to the west, the skull and lower jaws of the crocodylomorph Metriorhynchus were discovered by an honorary member of the LWL Museum für Naturkunde.
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In contrast, Erlikosaurus and Segnosaurus were aided by the down-turned tip of the lower jaws and symphyseal (bone union) regions, and probably also by stress and strain-mitigating beaks. The results also showed a difference in bite forces between Segnosaurus and Erlikosaurus, indicating the former would have been able to feed on tougher vegetation, while the overall robustness of the latter suggests greater flexibility in its manner of feeding. Lautenschlager pointed out the two taxa were adapted to different modes food acquisition, and that the difference in size and heights between the two therizinosaurids further separated their niches. While Segnosaurus was adapted to use its specialized dentition to procure or process food, Erlikosaurus mostly relied on its beak and neck musculature for cropping while foraging.
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Livyatan was part of a fossil stem group of hyper-predatory sperm whales commonly known as macroraptorial sperm whales, or raptorial sperm whales, alongside the extinct whales Brygmophyseter, Acrophyseter, and Zygophyseter. This group is known for having large, functional teeth in both the upper and lower jaws, which were used in capturing large prey, and had an enamel coating. Conversely, the modern sperm whale (Physeter macrocephalus) lacks teeth in the upper jaw, and the ability to use its teeth to catch prey. Livyatan belongs to a different lineage in respect to the other raptorial sperm whales, and the size increase and the development of the spermaceti organ, an organ that is characteristic of sperm whales, are thought to have evolved independently from other raptorial sperm whales.
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Overall, the fossa has features in common with three different carnivoran families, leading researchers to place it and other members of Eupleridae alternatively in Herpestidae, Viverridae, and Felidae. Felid features are primarily those associated with eating and digestion, including tooth shape and facial portions of the skull, the tongue, and the digestive tract, typical of its exclusively carnivorous diet. The remainder of the skull most closely resembles skulls of genus Viverra, while the general body structure is most similar to that of various members of Herpestidae. The permanent dentition is (three incisors, one canine, three or four premolars, and one molar on each side of both the upper and lower jaws), with the deciduous formula being similar but lacking the fourth premolar and the molar.
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The lower jaws of Megamastax (F,G) compared to other Silurian jawed fish Although Megamastax can be safely considered a sarcopterygian (lobe-finned fish) due to having cosmine on its jaws, coronoid plates, a prearticular bone, and a biconcave glenoid, it is unique among early jawed fish for its jaw and teeth structure. Although most early osteichthyans have only one row of sharp marginal teeth along the edge of the jaw, Megamastax has two rows of small marginal teeth. In addition, Megamastax uniquely has a row of large, blunt teeth fused to four coronoid bones on the inside edge of each mandible. Similar genera such as Psarolepis and Guiyu have sharp fangs on their five coronoids while poroplepiformes and tetrapodomorphs have tusk-like teeth and three coronoids.
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Beds of the upper Fruitland Formation and lower Kirtland Formation in the vicinity of the Titanoceratops holotype quarry J. Willis Stovall holds up the humerus, 1941 The holotype of Titanoceratops was collected from the upper Fruitland Formation or the lower Kirtland Formation in July 1941, by a field crew consisting J. Willis Stovall, his student Wann Langston Jr., and Donald E. Savage. The precise location of the quarry is no longer known. The holotype specimen consists of most of the fore and hindlimbs, some vertebrae, a fairly complete skull with only one small section of the frill, and partial lower jaws. The bones, being preserved in a fine- grained shale, were crushed and fragile, and so the skeleton was initially considered unsuitable for mounting.
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Unlike the V-shaped mandibular symphysis of Luoyanggia, Nankangia and other oviraptorosaurs have a U-shaped mandibular symphysis. Although Nankangia and Jiangxisaurus possess similar lower jaws, the medial margin of the humerus is more curved medially in Nankangia than it is in Jiangxisaurus. Based on its phylogenetic position, Nankangia displays five other possible autapomorphies, including an anteriorly projecting acromion, separated anterior and greater trochanters, dorsoventral extension of the pubic peduncle that is deeper than the ischial peduncle, and the lack of a downturned symphyseal portion of the dentary. The latter trait is shared with the coeval Ganzhousaurus and Jiangxisaurus, suggesting a primarily herbivorous diet, whereas Banji and another unnamed oviraptorid from the same formation may have been more carnivorous, as they bear a downturned mandibular symphysis.
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Available in: Like many other ornithocheirids, Anhanguera had rounded crests at front of its upper and lower jaws, which were filled with angled, conical but curved teeth of various sizes and orientations. Like many of its relatives, the jaws were tapered in width, but expanded into a broad, spoon-shaped rosette at the tip. It is distinguished from its relatives by subtle differences in the crest and teeth: unlike its close relatives Coloborhynchus and Ornithocheirus, the crest on the upper jaw of Anhanguera did not begin at the tip of the snout, but was set farther back on the skull. Like many ornithocheiroids, (most notably the pteranodonts but also in ornithocheirids such as Ludodactylus) Anhanguera had an additional crest protruding from the back of the skull.
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The crests of thalassodromids appear to have developed late in growth (probably correlated with sexual maturity) and they may have been sexually dimorphic (differing according to sex). As the genus name implies, Thalassodromeus was originally proposed to have fed like a modern skimmer bird, by skimming over the water's surface and dipping its lower jaws to catch prey. This idea was later criticised for lack of evidence; Thalassodromeus has since been found to have had strong jaw musculature, and may have been able to kill and eat relatively large prey on the ground. The limb proportions of related species indicate that it may have adapted to fly in inland settings, and would have been efficient at moving on the ground.
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It contains both praemaxilla (frontmost upper jaw bones), both maxillae (main upper jaw bone), teeth, a lacrimal, a jugal, a postorbital, a squamosal, a supraoccipital, parts of the lower jaws, a possible hyoid, two cervical (neck) vertebrae (backbones), cervical ribs, rear dorsal (back) vertebrae, at least five front caudal (tail) vertebrae, chevrons, ribs, gastralia (or "belly ribs"), the lower parts of a left forelimb, a furcula (wishbone), both pubic bones, a left ischium (lower and rearmost hip bone), a right femur, a tibia (shin bone), the upper part of a fibula (calf bone), a left astragalus (ankle bone), three tarsals, and three metatarsals. About 40% of the skeleton is presented. Dracoraptor is thus the most complete Mesozoic non-bird theropod dinosaur known from Wales.
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Returning to Edinburgh Nasmyth was elected a Fellow of the Royal College of Surgeons of Edinburgh in 1823, submitting as his original work A probationary essay on tic douloureux, a form of facial pain. He set up practice as a dentist at 21, St Andrew Square in Edinburgh's New Town. His innovations included a cap splint, described by Liston in his textbook Practical Surgery. This was used for maxillary reconstruction after tumour excision and was "devised by my friend Mr. Nasmyth of Edinburgh... to have metal caps fitted to the teeth of the upper and lower jaws soldered or riveted together at their bases which shall have the effect when applied of preventing the remaining fragment of bone and chin being dragged to the opposite side".
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The "lower jaws" are modified versions of the opercula that protect the retracted lophophores in autozooids of some species, and are snapped shut "like a mousetrap" by similar muscles, while the beak-shaped upper jaw is the inverted body wall. In other species the avicularia are stationary box-like zooids laid the normal way up, so that the modified operculum snaps down against the body wall. In both types the modified operculum is opened by other muscles that attach to it, or by internal muscles that raise the fluid pressure by pulling on a flexible membrane. The actions of these snapping zooids are controlled by small, highly modified polypides that are located inside the "mouth" and bear tufts of short sensory cilia.
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Warrenisuchus is known from several fossil specimens. The holotype skeleton preserves most of the skull and lower jaws, the pectoral girdle, the forward-most vertebrae and ribs, and the right hind limb and the paratype specimen includes a partial skull and pectoral girdle. All known specimens of Warrenisuchus are very small; the largest skull is only long and the smallest is long (adult capitosaurs can have skulls over a meter in length). They show many characteristics of juvenile individuals such as large eye sockets, rounded heads (adult capitosaurs typically have triangular heads), loose joints between skull bones, small tabular horns, and pineal foramina close to the back of the eye sockets (as opposed to farther back on the skull table).
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They also suggested that R. gracilis, not included in the analysis, might be the sister taxon of C. bonapartei, based on morphology, further supporting the exclusion of P. ischigualastensis from Chanaresuchus. Trotteyn and Ezcurra (2014) distinguished P. ischigualastensis from other proterochampsids, including C. bonapartei, based on a unique combination traits. These include a transversely broad basicranium with transversely oriented basal tubera, paroccipital processes with vertically expanded far end, the absence of a retroarticular projection on the lower jaws, tail vertebrae with a mid longitudinal groove on the bottom surface of the centrum and with pre- and post-zygapophyses strongly divergent from the midline, the lack of foramina on the back groove of the astragalus, and finally, osteoderm ornamentation consisting solely of longitudinal grooving.
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The reptilian quadrate bone, articular bone, and columella evolved into the mammalian incus, malleus, and stapes (anvil, hammer, and stirrup), respectively. In reptiles, the eardrum is connected to the inner ear via a single bone, the columella, while the upper and lower jaws contain several bones not found in mammals. Over the course of the evolution of mammals, one bone from the lower and one from the upper jaw (the articular and quadrate bones) lost their purpose in the jaw joint and migrated to the middle ear. The shortened columella connected to these bones within the middle ear to form a chain of three bones, the ossicles, which serve to effectively transmit air-based vibrations and facilitate more acute hearing.
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Kielan-Jaworowska, Zofia, Richard L. Cifelli, and Zhe-Xi Luo (2005). Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure , p. 299 Multituberculates are notable for the presence of a massive fourth lower premolar, the plagiaulacoid; other mammals, like Plesiadapiformes and diprotodontian marsupials, also have similar premolars in both upper and lower jaws, but in multituberculates this tooth is massive and the upper premolars aren't modified this way. In basal multituberculates all three lower premolars were plagiaulacoids, increasing in size posteriorly, but in Cimolodonta only the fourth lower premolar remained, with the third one remaining only as a vestigial peg-like tooth, and in several taxa like gondwanatherians and taeniolabidoideans, the plagiaulacoid disappeared entirely or was reconverted into a molariform tooth.
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Frič (1883) considered these fangs to have grown out of the vomers (from the front of the skull) or possibly the parasphenoid (from the back of the skull), but Carroll (1966) reconstructed the fangs as being part of the long pterygoid bones, which were originally reported as being toothless. This is consistent with the relationship between Boii and Asaphestera, as the latter possessed two fangs along the outer edge of each pterygoid about midway down the skull. The dentaries (main bones of the lower jaws) are also preserved and covered with teeth similar to those of the upper jaws. A row of small pits run from the symphysis (chin) along the upper portion of the outer face of the bones.
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It contains the right premaxilla, both maxillae, the left jugal, a part of the right lacrimal, the rear of a left nasal bone, the middle part of a right nasal bone, the skull roof from the frontal bones to the exoccipitals, both squamosals, both quadrate bones, the predentary of the lower jaws, both dentaries, a right surangular, eleven neck vertebrae, eleven back vertebrae, twenty-nine tail vertebrae, nineteen chevron bones, nineteen ribs, the entire pelvis, both lower legs, a right second metatarsal and a right fourth metatarsal. The bones have not been found in articulation. Specimen MOR 1097, a fragmentary skull of a subadult individual, was referred to the species. It had been found at a kilometre distance from the holotype.
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It is elongated and triangular in side view. The snout is appending with a slight kink above the middle of the fossa antorbitalis, which at this point is reinforced by a distinctive vertical bone strut, a pila interfenestralis dividing the depression in two halves: at its rear an oval skull opening, the fenestra antorbitalis, pierces the surface and at its front the uniquely large and deep hollowing out of the maxilla side is visible, in which another opening, the fenestra maxillaris, might have been present, though this is uncertain because of damage. The front of the snout consists of a small praemaxilla, continuing the line of the nasals downwards and forming a small upper beak in front of the lower jaws.
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Both species of Laganosuchus are known only from their lower jaws, those of L. thaumastos almost complete save for the left retroarticular process and those of L. maghrebensis only from a fragment of the dentary bone. L. thaumastos had a total jaw length of 838 mm and a jaw length from tip to articular facet of 750 mm, of which 490 mm actually bore teeth. Across the jaws, the total width of the lower jaw ranged from around 140 mm at the symphysis to 240 mm at the articular facets, widening fairly evenly all the way along. All the teeth were simple straight spikes, with the first pair the largest and the rest of the teeth decreasing in size towards the back of the mouth.
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Their lower jaws usually have three rows of keradonts surrounded by a horny beak, but the number of rows can vary and the exact arrangements of mouth parts provide a means for species identification. In the Pipidae, with the exception of Hymenochirus, the tadpoles have paired anterior barbels, which make them resemble small catfish. Their tails are stiffened by a notochord, but does not contain any bony or cartilaginous elements except for a few vertebrae at the base which forms the urostyle during metamorphosis. This has been suggested as an adaptation to their lifestyles; because the transformation into frogs happens very fast, the tail is made of soft tissue only, as bone and cartilage take a much longer time to be broken down and absorbed.
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The shaft of the quadrate bone in the skull also straightened in adults, and the tips of their lower jaws became more downturned. The most obvious change that happened during the growth of Limusaurus was the complete loss of teeth from juveniles to adults. Juveniles began with one tooth in each premaxilla, eight in each maxilla, and at least twelve in each half of the lower jaw (at least 42 teeth in total). At the next stage, the first, sixth, and eighth teeth in each maxilla, as well as the sixth in each half of the lower jaw had all been lost, although the sockets were still present, and there was a small replacement tooth in the socket of the sixth lower tooth (leaving at least 34 teeth in total).
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The lips were once believed to be unable to function as a sucker while respiration continued, as the inflowing water would cause the system to fail; however, respiration and suction can function simultaneously. Inflowing water passing under the sucker is limited to a thin stream immediately behind each maxillary barbel; the maxillae in loricariids support only small maxillary barbels and are primarily used to mediate the lateral lip tissue in which they are embedded, preventing failure of suction during inspiration. To achieve suction, the fish presses its lips against the substrate and expands its oral cavity, causing negative pressure. Also, unlike most other catfishes, the premaxillae are highly mobile, and the lower jaws have evolved towards a medial position, with the teeth pointed rostroventrally; these are important evolutionary innovations.
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The material was very well preserved, generally preserving the three- dimensional shape of the bones with very little crushing or distortion in some of the specimens. Based on the state of preservation, some of the bones were believed to have been buried rapidly while others were exposed for longer on the surface, where they were weathered, cracked and possibly trampled on before burial. As with A. laaroussii, the teeth and jaws were the first material to be recovered and described from the bone bed. These were initially mistaken to belong two different species based on the difference in tooth shape in the upper and lower jaws, but one of them was recognised as closely resembling A. laaroussii, sharing a keel on the inside surface of the maxilla and expanded, leaf-shaped teeth, among other features.
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M. pristinus skull M. pristinus was first described and named by Maurice G. Mehl in 1928 as the type species of Pseudopalatus, Pseudopalatus pristinus, on the basis of the holotype MU 525, nearly complete skull. It was collected, from the Norian-aged Upper Petrified Forest Member of the Chinle Formation, near Adamana, Arizona. Additional skulls and postcranial material, some articulated skeletons, from the same member were referred to this species by Colbert (1946) and Long and Murry (1995) from Arizona, and by Lawler (1979), Ballew (1986) and Long and Murry (1995) from New Mexico. Charles Camp (1930) described and named Machaeroprosopus tenuis on the basis of UCMP 27018, a nearly complete skull, lower jaws, and some complete postcranial material, from the Billings Gap locality (UCMP 7043, Upper Petrified Forest Member), Apache County of Arizona.
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The holotype specimen of Manidens, MPEF-PV 3211, consists of a partial skeleton with skull and lower jaws, including the axial column except most of the tail; a left shoulder girdle; and the pelvis. The specimens MPEF-PV 1719, 1786, 1718, 3810, 3811, isolated posterior teeth, from the same locality and horizon as the holotype are also referred to this genus. The specimens were found in the Queso Rallado locality of the Cañadón Asfalto Formation, dating to the Aalenian–Early Bathonian stages, 171 ± 5 to 167 ± 4 Ma. Manidens was a relatively basal heterodontosaurid that grew to about in length, smaller than later heterodontosaurids. It has high-crowned teeth indicative of an increased adaptation to a herbivorous diet but lacks the wear facets seen in more advanced forms like Heterodontosaurus.
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Streptospondylus means "turned vertebra", and is derived from the Greek words streptos (στρεπτος) meaning "reversed" and spondylus (σπονδυλος), a reference to the fact that its dorsal vertebrae were opisthocoelous, in contrast to the typical procoelous vertebrae of crocodiles. The specific name "oxoniensis", refers to its provenance from Oxford. Von Huene's 1923 restoration of Streptospondylus cuvieri, which actually depicts Eustreptospondylus The holotype, OUM J13558, was recovered by W. Parker from claystone in a marine layer of the Stewartby Member of the Oxford Clay Formation, which dates to the Callovian stage of the Jurassic period, approximately 162 million years ago. It consists of a rather complete skeleton, with a skull which is missing elements including the nasal bones, the jugals, the rear ends of the lower jaws, the lower arms and the end of the tail.
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Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed; therefore, all teeth are visible, unlike an alligator, which possesses in the upper jaw small depressions into which the lower teeth fit. Also, when the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to- distinguish specimens, the protruding tooth is the most reliable feature to define the species' family. Crocodiles have more webbing on the toes of the hind feet and can better tolerate saltwater due to specialized salt glands for filtering out salt, which are present, but non-functioning, in alligators.
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Lockheed's appearance and character, as depicted by the various artists who illustrated him and writer Chris Claremont, evolved from the time of his first appearance to his later appearances in Excalibur. When he first appeared as drawn by Paul Smith, he was largely quadrupedal, with red eyes lacking any pupils or irises, a small triangular head about half a foot long, and teeth protruding outward from his upper and lower jaws, and his intelligence appeared comparable with that of a dog. By the time of his appearances in Excalibur as drawn by Alan Davis, he had been anthropomorphized considerably. His eyes were now human-like, with white corneas and black irises, though at times they were colored yellow and red or orange and he was capable of more human-like facial expressions and gestures, including standing on his hind legs.
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These differentiations include the relatively indistinct and symmetrical teeth with moderate serrations (denticles) in Erlikosaurus, and the enlarged serrations in Segnosaurus composed of additional carinae and folded carinae with denticulated front edges, which together created a roughened, shredding surface near the base of the tooth crowns that was apparently unique to Segnosaurus and suggest they consumed unique food resources or used highly specialized feeding strategies, and had a higher degree of oral food processing than other therizinosaurids. In addition to these morphological differences, in 2019 Button and Zanno note that herbivorous dinosaurs followed two main distinct modes of feeding. One of these was processing food in the gut which is characterized by gracile skulls and relatively low bite forces. The second was oral food processing, characterized by features associated with extensive processing such as the lower jaws or dentition.
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Lower jaw of Erlikosaurus (bottom) and Segnosaurus (top) Erlikosaurus lived alongside a larger species of therizinosaurid in the Bayan Shireh Formation, Segnosaurus. In 2016, Zanno and colleagues re-examined the lower jaws and dentition of Segnosaurus making direct comparisons with those of Erlikosaurus in the process. They identified rather complex features in the dentary teeth of Segnosaurus, which are represented by the presence of numerous carinae (cutting edges) and folded carinae with denticulated front edges, and the enlargement of denticles (serrations). These traits together create a roughened, shredding surface near the base of the tooth crowns that was unique to Segnosaurus and suggest it consumed unique food resources or used highly specialized feeding strategies, with the addition of a higher degree of oral food processing than the sympatric—related species that lived in the same area at the same time—Erlikosaurus.
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This animal also had a rather short neck and robust projections of the back vertebrae for muscle attachment, indicating that the neck was used in vigorous exertions, probably during feeding. Scale chart of B. salgadoi Bonitasaura also shows that some lines of titanosaurian evolution converged with diplodocids, namely low long skulls without the characteristic nasal arches of other macronarians (such as Brachiosaurus or Camarasaurus) and lower jaws that were squared off and contained comb-like teeth (as in Rebbachisauridae), reversed limb proportions (the front limbs shorter than the hind limbs, unlike the condition in most other macronarians) and rudimentary whiplash tails. It also threw a wrench into the suggestion by some authors (McIntosh 1990; Jacobs et al. 1993; Upchurch 1999) that the titanosaur Antarctosaurus is a chimera made up of a titanosaurian skull and body and a diplodocoid jaw.
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The holotype of Dromicosuchus is a partial skeletonUNC 15574. including a nearly complete skull and lower jaws, articulated vertebrae from the atlas to the second tail vertebra, bony armor from the back, ribs and the dermal bones called gastralia, partial shoulder girdles, most of the left arm and leg, and the right upper arm, thigh bone, and shin bone. It was found with the fossils of several other animals in a brick-clay quarry in Durham County, North Carolina, in blocks excavated by University of North Carolina at Chapel Hill students in fall 1994. The fossils came from a mudstone next to a river channel deposit, in Lithofacies Association II of the Deep River basin, part of the extensive Newark Supergroup, dated as pertaining to either the late Carnian or early Norian faunal stages of the Late Triassic.
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Among the recovered bones were most of the snout, a right postorbital, both angulars of the lower jaws, fifteen neck vertebrae (the first two, which articulated with the skull, were absent), two anterior dorsal vertebrae, twelve ribs, a chevron, the shoulder bones, most of the forelimbs including a possible os carpi intermedium, a right first metacarpal and three first phalanges; and thirteen bony plates plus a spike. The bones were not articulated but dispersed over a surface of about five to seven metres, though there was a partial concentration of fossils that could be salvaged within a single block. ML 433 was found in the Miragaia Unit of the Sobral Unit, Lourinhã Formation, which dates to the late Kimmeridgian-early Tithonian (Late Jurassic, approximately 150 million years ago). Octávio Mateus, Susannah Maidment and Nicolai Christiansen named and briefly described Miragaia in 2009.
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Casts of the vertebrae seen from behind Though no skull remains have been found for Ichthyovenator, all known spinosaurids had elongated, low, narrow snouts that allowed them to reach far for food and to quickly close their jaws in a manner similar to modern crocodilians. The tips of spinosaurids' upper and lower jaws fanned out into a rosette-like shape that bore long teeth, behind which there was a notch in the upper jaw; this formed a natural trap for prey. Like those of other spinosaurids, Ichthyovenators straight, unserrated teeth would have been suitable for impaling and capturing small animals and aquatic prey. This type of jaw and tooth morphology, which is also observed in today's gharials and other fish-eating predators, has led many palaeontologists to believe spinosaurids were largely piscivorous (as implied by Ichthyovenators name).
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A 2013 study by Lü and colleagues found that oviraptorids appear to have retained their hind limb proportions throughout ontogeny (growth), which is also a pattern mainly seen in herbivorous animals. In 2017, the Canadian palaeontologist Gregory F. Funston and colleagues suggested that the parrot- like jaws of oviraptorids may indicate a frugivorous diet that incorporated nuts and seeds. Diagrams showing the hands of specimen MPC-D 107/15 and 107/16 In 1977 Barsbold suggested that oviraptorids fed on molluscs, but Longrich and colleagues rejected the idea that they practised shell-crushing altogether, since such animals tend to have teeth with broad crushing surfaces. Instead, the shape of the dentary bones in the lower jaws of oviraptorids suggests they had a sharp-edged beak used for shearing tough food, not for cracking hard food items such as bivalves or eggs.
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Michonne makes her first appearance as a hooded figure near the end of the second-season finale, "Beside the Dying Fire" (though at the time Danai Gurira had not been cast for this role), wherein she saves Andrea from a walker by decapitating it with her katana, which features a triquetra on the inner crossguard. As in the comics, she is accompanied by two chained walkers, side by side with their arms and lower jaws removed to prevent them from attacking. In removing their ability to eat, Michonne effectively tamed these walkers. Michonne has demonstrated economic uses for her pet walkers, such as using them as human pack mules by loading supplies onto their backs as well as a camouflage/repellent, as their presence and scent fools other walkers into thinking those accompanying them are also walkers.
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Liobagrus aequilabris is a species of catfish in the family Amblycipitidae (the torrent catfishes). This species is endemic to China, where it is only known from the Xiang River, a tributary of the Yangtze River, in Guangxi province, but may also be present in the Li River, a tributary of the Pearl River, due to the presence of the Lingqu Canal connecting the Xiang and Li Rivers. L. aequilabris reaches a length of SL. It differs from other members of its genus in lacking large, retrorse serrations on the posterior edge of the pectoral-fin spine, having upper and lower jaws of equal length, relatively long dorsal (7.5-10.2 % of SL) and pectoral-fin (9.1-12.1 % of SL) spines, a relatively long caudal fin (20.1-26.9 % of SL), and relatively few post-Weberian vertebrae (35-37).
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Pampadromaeus is known only from the holotype specimen ULBRA-PVT016, a disarticulated, partial but well preserved skeleton from a single individual which includes most of the skull bones and the lower jaws; dorsal, sacral and caudal vertebrae; elements of the shoulder girdle and the forelimbs, an ilium and elements of the hindlimbs. It was collected in the upper Hyperodapedon biozone from the Alemoa Member of the Santa Maria Formation (Rosário do Sul Group) in the "Janner" (also known as "Várzea do Agudo") locality, geopark of Paleorrota, dating to the Carnian faunal stage of the early Late Triassic, about 230–228 million years ago. A U-Pb (uranium decay) dating found that the Santa Maria Formation dated around 233.23 million years ago, putting it 1.5 million years older than the Ischigualasto Formation, and making the two formations approximately equal as the earliest dinosaur localities.Langer et al.
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Spinosaur jaws were likened by Romain Vullo and colleagues to those of the pike conger eel, in what they hypothesized was convergent evolution for aquatic feeding. Both kinds of animals have some teeth in the end of the upper and lower jaws that are larger than the others and an area of the upper jaw with smaller teeth, creating a gap into which the enlarged teeth of the lower jaw fit, with the full structure called a terminal rosette. Life restoration of Baryonyx with a fish in its jaws In the past, spinosaurids have often been considered piscivores (fish-eaters) in the main, based on comparisons of their jaws with those of modern crocodilians. In 2007, British paleontologist Emily J. Rayfield and colleagues conducted biomechanical studies on the skull of Baryonyx, which had a long, laterally compressed skull, comparing it to gharial (long, narrow, tubular) and alligator (flat and wide) skulls.
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The skeletons were discovered during eight seasons of fieldwork (2004–2012 field seasons) in the Slottsmøya Member, that have yielded other skeletal remains of marine reptiles, including the plesiosauroids Colymbosaurus svalbardensis, Djupedalia and Spitrasaurus, and the ichthyosaurs Cryopterygius and Palvennia. P. funkei was first described and named by Espen M. Knutsen, Patrick S. Druckenmiller and Jørn H. Hurum in 2012. The specific name honors Bjørn Funke, the discoverer of the holotype, and his wife May-Liss Knudsen Funke for volunteering in the paleontological collections at the Museum. Low resolution pdf The holotype of P. funkei is represented by the anterior portions of the upper and lower jaws (including premaxillary and dentary teeth), one nearly complete cervical centrum and two partial cervical centra, three pectoral centra with neural arches, fifteen dorsal centra and eight neural arches, a complete right coracoid, numerous rib fragments and gastralia, and a complete right forelimb.
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Larva of the long-toed salamander (Ambystoma macrodactylum) Larva of the long-toed salamander (Ambystoma macrodactylum) Larvae of the alpine newt (Ichthyosaura alpestris) At hatching, a typical salamander larva has eyes without lids, teeth in both upper and lower jaws, three pairs of feathery external gills, a somewhat laterally flattened body and a long tail with dorsal and ventral fins. The forelimbs may be partially developed and the hind limbs are rudimentary in pond-living species but may be rather more developed in species that reproduce in moving water. Pond-type larvae often have a pair of balancers, rod-like structures on either side of the head that may prevent the gills from becoming clogged up with sediment. Some members of the genera Ambystoma and Dicamptodon have larvae that never fully develop into the adult form, but this varies with species and with populations.
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Skull in multiple views Pseudochampsa is known solely from the holotype PVSJ 567, a nearly complete and articulated individual housed at the División de Paleontologia de Vertebrados del Museo de Ciencias Naturales y Universidad Nacional de San Juan, Argentina. The holotype consists of a skull with fully occluded lower jaws, a complete vertebral column lacking the outer half of the tail, several neck and back ribs, some haemal arches, some gastralia, the pectoral girdle, both partially preserved humeri, a partial pelvic girdle, and both nearly complete hind-limbs including both femora, tibiae, fibulae, tarsals and feet. PVSJ 567 was found at Valle Pintado, Hoyada de Ischigualasto of the Ischigualasto Provincial Park, San Juan Province. It was collected from the Cancha de Bochas Member of the Ischigualasto Formation, of Ischigualasto-Villa Union Basin, dating to the late Carnian to earliest Norian stages of the middle Late Triassic.
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Lower jaws of Erlikosaurus (bottom) and Segnosaurus (top) compared In 2009, Zanno and colleagues stated therizinosaurs were the most-widely regarded candidates for herbivory among theropods based on the small, densely packed, coarse serrations; lance-shaped teeth with a relatively low replacement rate; a well- developed keratinous beak; long neck for browsing; relatively small skulls; a very large gut capacity as indicated by the rib circumference at the trunk and the outwards flaring processes of the ilia; and the notable lack of cursorial adaptations in the hind limbs. All of these features suggest that members of this family feed on vegetation, as well as pre-processing it within their mouths to begin the breakdown of cellulose and lignin. This is perhaps even more so true for therizinosaurids, which seem to have further exploited these characters. One of the most notable adaptations in advanced therizinosaurids are the four-toed feet, which had a fully functional, weight-bearing first digit that was likely adapted to slow life-style.
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The study, when properly translated, refers to a feature, found in multiple horse breeds and perhaps all animals with sizable lower jaws, that appears to be an extra branch of blood supply in the area. While an extra tooth may have eventually developed from this extra blood supply, its frequency among the general horse population makes its appearance in the Exmoor pony unremarkable. The head is somewhat large in proportion to the body, with small ears, and has a unique feature called a "toad eye" caused by extra fleshiness of the eyelids, which helps to deflect water and provide extra insulation. As with most cold-weather pony breeds, the Exmoor grows a winter coat consisting of a highly insulating woolly underlayer and a topcoat of longer, oily hairs that prevent the undercoat from becoming waterlogged by diverting water down the sides of the animal to fall from just a few drip areas.
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Location and stratigraphy of the find An expedition from the New Mexico Museum of Natural History and Science and the State Museum of Pennsylvania, led by Robert Michael Sullivan, discovered a number of Z. sanjuanensis fossils in the Kirtland Formation in 2011. The specimens were found in the Hunter Wash and De-na-zin Members of the formation in the Bisti/De-Na-Zin Wilderness in New Mexico. Z. sanjuanensis was identified as a new species from a number of fossils including the holotype NMMNH P-64484 found from the De-na-zin Member and consisting of a complete skull lacking the lower jaws, parts of the first two cervical half-rings, and a number of partial osteoderms; and a referred specimen NMMNH P-66930 from the older Hunter Wash Member, consisting of a first cervical half-ring. By argon dating of ash layers the age of the holotype skull has been determined at between 72.98 and 72.62 million years old, the late Campanian.
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It includes the (lower jaws), an incomplete , a complete and (lower arm bones), of the fingers, a forelimb (claw bone), an almost-complete , an incomplete right , six , ten from the front of the tail, fifteen from the hindmost part of the tail, the first , and fragments of the dorsal ribs. Two more specimens were designated as paratype specimens; specimen IGM 100/82 from the Khara Khutul locality includes a femur, and (leg bones), and , five toe phalanges including a foot ungual, rib fragments, complete , the upper portion of an , and the lower portion of a . Specimen IGM 100/83 includes a left (shoulder girdle), a radius, an ulna, forelimb unguals, and a fragment of a (neck) vertebra. In 1980, Perle and the paleontologist Rinchen Barsbold assigned another specimen to Segnosaurus; IGM 100/81 from the Amtgay locality included a left tibia and fibula. In 1983, Barsbold listed additional specimens GIN 100/87 and 100/88.
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Lithograph of the holotype In 1874, Richard Owen named a pair of lower jaws from the collection of Samuel Husband Beckles, found at St Leonards-on-Sea in Sussex, as a new species of Pterodactylus: Pterodactylus sagittirostris. The specific name means "arrowhead-snouted" in Latin, referring to the mandible profile in upper view.Owen, R. 1874. "A Monograph on the Fossil Reptilia of the Mesozoic Formations. 1. Pterosauria." The Palaeontographical Society Monograph 27: 1–14 In 1888, Edwin Tulley Newton, conforming to the soon to be published pterosaur systematics by Richard Lydekker, renamed the species into Ornithocheirus sagittirostris.Newton, E. T., 1888, "On the Skull, Brain, and Auditory Organ of a new species of Pterosaurian (Scaphognathus purdoni), from the Upper Lias near Whitby, Yorkshire", Philosophical Transactions of the Royal Society of London, v. 179, p. 503-537 In July 1891, the British Museum (Natural History), the present Natural History Museum, bought the piece from the heirs of Beckles.
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Skull of Tongtianlong limosus Tongtianlong was a sheep-sized member of the oviraptorids, a group of omnivorous, feathered, bird-like theropods. The describers of Tongtianlong recognized that it possessed a set of distinctive characteristics that differentiated it both from other oviraptorosaurs. In particular, unlike other oviraptorids, the crest of Tongtianlong was shaped like a dome, with its highest point just behind the eye socket; and the front edge of the toothless premaxilla, which would have supported its beak, was very rounded. Additionally, there is a distinct ridge on the front margin of the parietal bone, wedged between the frontal bones; the shaft of the lacrimal bone, which is located in front of the eye socket, is wide, flattened, and plate-like seen from the side; the foramen magnum (a hole in the back of the skull) is smaller than the occipital condyle (the boss forming the skull-neck joint); there is no ridge on the bottom of the front lower jaws, which is also not strongly downturned; and the xiphoid process does not flare out from the sternum behind the ribs.
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The holotype, YPM 1876, was found in a layer of the Upper Brushy Basin Member of the Morrison Formation, dating from the Tithonian. It consists of a partial skeleton including a rather complete skull and lower jaws. Several other fossils from Wyoming have been referred to Dryosaurus altus. They include specimens YPM 1884: the rear half of a skeleton; AMNH 834: a partial skeleton lacking the skull from the Bone Cabin Quarry; and CM 1949: a rear half of a skeleton dug up in 1905 by William H. Utterback. From 1922 onwards in Utah, Earl Douglass discovered Dryosaurus remains at the Dinosaur National Monument. These include CM 11340: the front half of a skeleton of a very young individual; CM 3392: a skeleton with skull but lacking the tail; CM 11337: a fragmentary skeleton of a juvenile; and DNM 1016: a left ilium dug up by technician Jim Adams.Gilmore C.W., 1925, "Osteology of ornithopodous dinosaurs from the Dinosaur National Monument, Utah. Camptosaurus medius, Dryosaurus altus, Laosaurus gracilis", Memoirs of the Carnegie Museum 10: 385-409 Other fossils were found in Colorado.
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478 pp It more likely belongs to some member of the Coelophysoidea or Neoceratosauria. It has also been established by Newman and confirmed by Roger Benson that the original left thigbone, GSM 109560, belonged to a theropod.Benson, R., 2010, "The osteology of Magnosaurus nethercombensis (Dinosauria, Theropoda) from the Bajocian (Middle Jurassic) of the United Kingdom and a re-examination of the oldest records of tetanurans", Journal of Systematic Palaeontology 8(1): 131-146 Restoration of the skeleton by O.C. Marsh, showing the long legs at the time presumed for Scelidosaurus The neotype skeleton had been uncovered in the Black Ven Marl or Woodstone Nodule Bed, marine deposits of the Charmouth Mudstone Formation, dating from the late Sinemurian stage, about 191 million years ago.Barrett, P.M. and Maidment, S.C.R., 2011, "Dinosaurs of Dorset: Part III, the ornithischian dinosaurs (Dinosauria, Ornithischia) with additional comments on the sauropods", Proceedings of the Dorset Natural History and Archaeological Society 132: 145–163 It consists of a rather complete skeleton with skull and lower jaws.
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This ignorance of diet is partly due to the potential prevalence of regurgitation among net caught specimens, where nearly 100% of net caught daggertooths were documented with completely empty stomachs, the supposed reason being the regurgitation of freshly eaten food upon capture in nets as a defense mechanism. They are likely visually based predators and adult individuals can easily engulf relatively large prey, fishes with 20–30 cm fork length, whole due to their unattached pectoral girdles and distensible stomachs. Observations of slash marks on numerous young Pacific salmon in the northern Pacific prompted an investigation into the potential impact of daggertooth depredation on young salmon stocks by assessment of the tooth marks left on the salmon and estimations of daggertooth abundance. The subsequent findings showed that slashes from failed daggertooth attacks could be distinguished from failed lancetfish attacks by the placement of the tooth marks, as daggertooths only have fang-like teeth along their upper jaw while lancetfish have fang like teeth along both the upper and lower jaws.
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It includes an incomplete skull and mandible (lower jaws) and much of the postcranial skeleton, i.e. the parts behind the head. The skull of Tanycolagreus is less well known than its postcranial anatomy, and only the following elements have been found: left nasal, left lacrimal, left premaxilla and one premaxillary tooth, left postorbital, left quadratojugal, incomplete left squamosal, right quadrate, right splenial, left articular, and two cheek teeth. A paratype has been assigned to the species: specimen AMNH 587 consisting of an incomplete hand also collected from Bone Cabin Quarry and originally in 1903 by Henry Fairfield Osborn referred to Ornitholestes hermanni.Osborn, Henry Fairfield, 1903, "Ornitholestes hermanni, a new compsognathoid dinosaur from the Upper Jurassic", Bulletin of the American Museum of Natural History 19(12): 459–464 Two other fossils have been referred to Tanycolagreus: UUVP 2999, a premaxilla, originally in 1974 referred to Stokesosaurus clevelandi,Madsen, J., 1974, "A new theropod dinosaur from the Upper Jurassic of Utah", Journal of Paleontology, 48: 27-31 from the Cleveland-Lloyd Quarry of Utah; and USNM 5737, a pair of distal pubes from Colorado earlier in 1920 by Charles Whitney Gilmore referred to Coelurus.
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The specific name refers to its origin in Soria. The fossils, with catalogue numbers MNS 2000/132, 2001/122, 2002/95, 2003/69, 2004/54, were found in the Golmayo Formation which dates from the Hauterivian - Barremian, about 130 million years old. It consists of a partial skeleton with skull and lower jaws. Have been preserved: parts of the maxilla, a piece of premaxilla, a left dentary piece, a piece of the right surangular, pieces of the hyoid apparatus, loose edges of alveolar ridge, sixty two loose teeth from the upper jaw, thirty-six loose teeth from the lower jaw, a proatlas, a centrum of a cervical vertebra, a neck rib, four dorsal vertebrae, thirty-six pieces of the sacrum, thirty-two caudal vertebrae, six ribs, three complete chevrons, pieces of chevrons, ossified tendons, the right shoulder blade (scapula), both coracoids, both humeri, the right-hand radius, the left ulna, the right hand thumb, the right hand, a piece of left iliac, the processus praepubici of the two pubic bones, a piece of the right femur, a part of the right tibia, and the second and fourth metatarsals of the right leg.
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It is part of the collection of the Denver Museum of Nature and Science after which the genus was named. Bakker referred a second fossil to the species, specimen AMNH 3076, a skull found by Brown and American Museum of Natural History paleontologist Roland T. Bird at the Tornillo Creek in Brewster County, Texas, in a layer of the poorly dated Upper Cretaceous Aguja Formation, possibly from the Maastrichtian also. Scientists at the Black Hills Institute found a nodosaurid skeleton in Niobrara County, Wyoming, nick-named "Tank", which has been identified as Denversaurus. The specimen contains the lower jaws, parts of the torso and about a hundred osteoderms. It is part of the collection of the Rocky Mountain Dinosaur Resource Center under inventory number BHI 127327.Carpenter K., DiCroce T., Kinneer B., Simon R., 2013, "Pelvis of Gargoyleosaurus (Dinosauria: Ankylosauria) and the Origin and Evolution of the Ankylosaur Pelvis", PLoS ONE 8(11): e79887. The validity of Denversaurus was disputed in a 1990 paper on ankylosaurian systematics by Kenneth Carpenter, who noted that Bakker's diagnosis of Denversaurus was based primarily on Bakker's artistic restoration of the holotype in an uncrushed state. Since DMNH 468 was found crushed, Carpenter assigned Denversaurus to a Edmontonia sp.
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