"The ceratopsian line will likely be next if the raptors get the go ahead," Silva said.
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He later found a suitcase-size piece of fossilized skin from a ceratopsian attached to the hip bone.
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Silva is already toying with the idea of putting together a similar series on ceratopsian dinosaurs, the group of horned herbivores that includes heavyweights like Triceratops, Styracosaurus, and Regaliceratops.
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When DePalma first visited the site, he noted, partially embedded on the surface, the hip bone of a dinosaur in the ceratopsian family, of which triceratops is the best-known member.
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A nocturnal lifestyle has been suggested for the primitive ceratopsian Protoceratops.Longrich, N. (2010). "The Function of Large Eyes in Protoceratops: A Nocturnal Ceratopsian?", In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, 656 pp. .
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Yinlong (隱龍, meaning "hidden dragon") is a genus of basal ceratopsian dinosaur from the Late Jurassic Period of central Asia. It was a small, primarily bipedal herbivore. Yinlong is the oldest and most primitive ceratopsian known.
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It is also probably represents the smallest adult-sized ceratopsian known from North America.
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Eberth, Brinkman, and Barkas also noted the presence of two beds in the mudstone hosting the Hilda bonebeds that weren't ceratopsian bonebeds, but rather they contained vertebrate microfossils. The first of these was H97-09, a natural part of the same stratum that hosted the ceratopsian bonebeds, but bearing only the remains of aquatic animals like champsosaurs, crocodilians, fish, and turtles. The second was a lens of sandstone that formed after the ceratopsian bonebeds cataloged as H97-12. This lens of sandstone penetrated down into the bed that hosted the ceratopsian bonebeds, probably deposited by a creek.
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It would have used its sharp Ceratopsian beak to bite off the leaves or needles.
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Wendiceratops is a genus of herbivorous centrosaurine ceratopsian dinosaur from the Late Cretaceous of Canada.
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Breviceratops (meaning "short horn face") was a herbivorous ceratopsian dinosaur from the Late Cretaceous of Mongolia.
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Spinops is an extinct genus of centrosaurine ceratopsian dinosaur from the Late Cretaceous of Alberta, southern Canada.
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Gryphoceratops is an extinct genus of leptoceratopsid ceratopsian dinosaur known from the Late Cretaceous of Alberta, southern Canada.
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Bainoceratops (Bain: mountain, keras: horn, ops: face) is a genus of ceratopsian dinosaur from the late Campanian in the Late Cretaceous. This ceratopsian was first described by Tereschenko and Alifanov in 2003 and the type species is B. efremovi. Its fossils were found in southern Mongolia in the Djadochta Formation.
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Originally referred as a ceratopsian by Tapia in 1918, it was later dismissed because no other members of that group were known from the Southern Hemisphere. However, the 2003 discovery of another possible ceratopsian, Serendipaceratops, from Australia could change this view. T. Rich and P. Vickers-Rich. 2003. Protoceratopsian? ulnae from Australia.
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It would have used its sharp ceratopsian beak to bite off the leaves or needles. Its habitat was densely forested.
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Vagaceratops (meaning "wandering (vagus, Latin) horned face", in reference to its close relationship with Kosmoceratops from Utah) is a genus of herbivorous ceratopsian dinosaur. It is a chasmosaurine ceratopsian which lived during the Late Cretaceous period (late Campanian) in what is now Alberta. Its fossils have been recovered from the Upper Dinosaur Park Formation.
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Diabloceratops [dee-ab-lo-ser-a-tops] is an extinct genus of centrosaurine ceratopsian dinosaur that lived approximately 79.9 million years ago during the latter part of the Cretaceous Period in what is now Utah, in the United States.Kirkland, J.I. and DeBlieux, D.D. (2010). "New basal centrosaurine ceratopsian skulls from the Wahweap Formation (Middle Campanian), Grand Staircase–Escalante National Monument, southern Utah", In: Ryan, M.J., Chinnery-Allgeier, B.J., and Eberth, D.A. (eds.) New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium. Bloomington, Indiana University Press, pp.
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Skeletal mount of Titanoceratops This timeline of ceratopsian research is a chronological listing of events in the history of paleontology focused on the ceratopsians, a group of herbivorous marginocephalian dinosaurs that evolved parrot-like beaks, bony frills, and, later, spectacular horns. The first scientifically documented ceratopsian fossils were described by Edward Drinker Cope starting in the 1870s; however, the remains were poorly preserved and their true nature was not recognized. Over the next several decades, Cope named several such genera and species. Cope's hated rival, Othniel Charles Marsh, also described ceratopsian remains.
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V. osmolskae lived alongside the ceratopsian species Magnirostris dodsoni, as well as the oviraptorid Machairasaurus leptonychus and the dromaeosaurid Linheraptor exquisitus.
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An extremely rare Maastrichian ceratopsian tooth was found in 2016, making it the third ceratopsian remain known from Appalachia. In the early Cenozoic, southern Mississippi was sometimes inundated by a tropical sea. During the Paleocene epoch, Clay County was home to foraminiferans and ostracods. Bony fish, sharks, and whales also lived in the early Cenozoic seas of Mississippi.
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In 1887, Marsh mistook a Triceratops horn for one belonging to a new species of prehistoric Bison. Marsh also named the eponymous genus Ceratops in 1888. The next year, he named the most famous ceratopsian, Triceratops horridus. It was the discovery of Triceratops that illuminated the ceratopsian body plan, and he formally named the Ceratopsia in 1890.
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Lehman, T.M. 1990. The ceratopsian subfamily Chasmosaurinae: sexual dimorphism and systematics. In: Carpenter, K. & Currie, P.J. (Eds.). Dinosaur Systematics: Approaches and Perspectives.
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Microceratops is a genus of ichneumonid wasp. The name was intermittently applied to a genus of ceratopsian dinosaur before this was renamed.
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"The ceratopsian subfamily Chasmosaurinae: sexual dimorphism and systematics". In: Carpenter, K. & Currie, P.J. (Eds.). Dinosaur Systematics: Approaches and Perspectives. Cambridge: Cambridge University Press.
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In 1914, a new ceratopsian dinosaur found by Lawrence Lambe was again given the name Protorosaurus (in this sense meaning "before Torosaurus"). When Lambe found that the name had already been used for the early archosauromorph, he renamed his ceratopsian Chasmosaurus. In Geopark of Paleorrota, Rio Grande do Sul, Brazil, 3 vertebrae and some bones of the animal were found.
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Unescoceratops is a genus of leptoceratopsid ceratopsian dinosaurs known from the Late Cretaceous of Alberta, southern Canada. It contains a single species, Unescoceratops koppelhusae.
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Titanoceratops (meaning "titanic horn face") is a genus of herbivorous ceratopsian dinosaur. It was a giant chasmosaurine ceratopsian that lived in the Late Cretaceous period (Campanian stage, about 75 million years agoFowler, D. W. 2017. Revised geochronology, correlation, and dinosaur stratigraphic ranges of the Santonian-Maastrichtian (Late Cretaceous) formations of the Western Interior of North America. PLoS ONE 12(11): e0188426.) in what is now New Mexico.
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Ostrom suggested that Deinonychus could kick with the sickle claw to cut and slash at its prey. Some researchers even suggested that the talon was used to disembowel large ceratopsian dinosaurs.Adams, Dawn (1987) "The bigger they are, the harder they fall: Implications of ischial curvature in ceratopsian dinosaurs" pp. 1–6 in Currie, Philip J. and Koster, E. (eds) Fourth symposium on mesozoic terrestrial ecosystems.
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Microceratus (meaning "small-horned") is a genus of small ceratopsian dinosaur that lived in the Cretaceous period in Asia. It walked on two legs, had short front arms, a characteristic ceratopsian frill and beak-like mouth, and was around long. It was one of the first ceratopsians, or horned dinosaurs, along with Psittacosaurus in Mongolia. The type species, Microceratops gobiensis, was first described by Bohlin in 1953.
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Spiclypeus (meaning "spike shield") is an extinct genus of chasmosaurine ceratopsian dinosaur known from the Late Cretaceous Judith River Formation (late Campanian stage) of Montana, United States.
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Unlike almost all other dinosaur groups, skulls are the most commonly preserved elements of ceratopsian skeletons and many species are known only from skulls. There is a great deal of variation between and even within ceratopsian species. Complete growth series from embryo to adult are known for Psittacosaurus and Protoceratops, allowing the study of ontogenetic variation in these species. Significant sexual dimorphism has been noted in Protoceratops and several ceratopsids.
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Records of the Queen Victoria Museum Launceston 113:1-12 Notoceratops has since been considered a nomen dubium and may have been a hadrosaur instead. An analysis published by Tom Rich et al. in 2014, which focused on the validity of another supposed southern ceratopsian, Serendipaceratops, also examined the published material from Notoceratops. They concluded that the holotype had ceratopsian features and that the genus is probably valid.
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The largest ceratopsian known is Triceratops horridus, along with the closely related Eotriceratops xerinsularis both with estimated lengths of . Ojoceratops and several other ceratopsians rival them in size.
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The combination is in reference to the lack of ceratopsian species known from the Foremost Formation. The specific epithet foremostensis is named after the town of Foremost, Alberta.
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Aquilops is an early herbivorous ceratopsian dinosaur dating from the Early Cretaceous of North America, approximately 108 million to 104 million years ago. The type species is A. americanus.
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Triceratops is by far the best-known ceratopsian to the general public. It is traditional for ceratopsian genus names to end in "-ceratops", although this is not always the case. One of the first named genera was Ceratops itself, which lent its name to the group, although it is considered a nomen dubium today as its fossil remains have no distinguishing characteristics that are not also found in other ceratopsians.Dodson, P. 1996.
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An age determination study performed on the fossilized remains of P. mongoliensis by using growth ring counts suggest that the longevity of the basal ceratopsian was 10 to 11 years.
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Ceratopsidae is the most advanced group of Ceratopsians The first ceratopsian remains known to science were discovered during the U.S. Geological and Geographical Survey of the Territories led by the American geologist F.V. Hayden. Teeth discovered during an 1855 expedition to Montana were first assigned to hadrosaurids and included within the genus Trachodon. It was not until the early 20th century that some of these were recognized as ceratopsian teeth.Hatcher, J.B., Marsh, O.C. and Lull, R.S. (1907).
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Tatankaceratops (meaning "Bison horn face") is a controversial genus of herbivorous ceratopsian dinosaur. It is a small chasmosaurine ceratopsian which lived during the Late Cretaceous period (latest Maastrichtian stage) in what is now South Dakota. It is known from a single partial skull which was collected from the Hell Creek Formation, dating to 66 million years ago. Tatankaceratops was described by Christopher J. Ott and Peter L. Larson in 2010 and the type species is Tatankaceratops sacrisonorum.
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Udanoceratops (meaning "Udan-Sayr horn face") is an extinct genus of leptoceratopsid ceratopsian dinosaur. It lived during the Late Cretaceous Period in the Campanian faunal stage. Its fossils were found in Mongolia.
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In ceratopsian dinosaurs, it opposed the rostral bone. In 2017 Baron & Barrett suggested that Chilesaurus may represent an early diverging ornithischian that had not yet acquired the predentary of all other ornithischians.
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Centrosaurus ( ) is a genus of herbivorous ceratopsian dinosaurs from the Late Cretaceous of Canada. Their remains have been found in the Dinosaur Park Formation, dating from 76.5 to 75.5 million years ago.
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C.A. Forster, however, found no evidence of large muscle attachments on the frill bones.Forster, C. A. (1990). The cranial morphology and systematics of Triceratops, with a preliminary analysis of ceratopsian phylogeny. Ph.D. Dissertation.
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Eotriceratops (meaning "dawn three-horned face") is a genus of herbivorous ceratopsian dinosaurs which lived in the area of North America during the late Cretaceous period. The only named species is Eotriceratops xerinsularis.
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The genus Unescoceratops was first described by Michael J. Ryan, David C. Evans, Philip J. Currie, Caleb M. Brown and Don Brinkman in 2012 (though it had been published earlier by Ryan and Currie in 1995 with no name) and the type species is Unescoceratops koppelhusae. The name means "UNESCO's ceratopsian" (ceratopsian means "one with a horned face"). The name is meant to honor UNESCO's efforts to increase understanding of natural history sites around the world. "Dinosaurprovincialparkaceratops was too long," explained Ryan.
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It has been claimed that ceratopsian dinosaurs were herding animals, due to the large number of known bone beds containing multiple members of the same ceratopsian species. In 2010, Hunt and Farke pointed out that this was mainly true for centrosaurine ceratopsians. Horner assumed that the horned dinosaurs at Landslide Butte lived in herds which had been killed by drought or disease. Dodson concluded that the fact that the Achelousaurus bone beds were monospecific (containing only one species) confirmed the existence of herds.
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Dinosaurs contemporaneous with Xiyunykus in the Tugulu Group of Xinjiang include the stegosaur Wuerhosaurus, the coeval alvarezsaur Tugulusaurus, the carcharodontosaurid Kelmayisaurus, the dubious maniraptoran Phaedrolosaurus, the problematic coelurosaur Xinjiangovenator, and the ceratopsian Psittacosaurus xinjiangensis.
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The fossils most closely resemble those of the Asian bagaceratopsids Bagaceratops and the Magnirostris. Those similarities indicate Ajkaceratops is a ceratopsian related to the bagaceratopsids, but more primitive than the Zuniceratops and the Ceratopsidae.
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The body was long and flat, suitable for gliding. The skull was lizard-like with a pointed snout and contained a broad back with a serrated crest, superficially resembling the crests of ceratopsian dinosaurs.
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Pp. 517–606 Full text.Xu X., Forster, C.A., Clark, J.M., & Mo J. (2006). "A basal ceratopsian with transitional features from the Late Jurassic of northwestern China." Proceedings of the Royal Society B: Biological Sciences. .
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Machairoceratops (meaning bent sword horned face) is an extinct genus of centrosaurine ceratopsian dinosaur known from the Late Cretaceous Wahweap Formation (late Campanian stage) of Grand Staircase-Escalante National Monument, southern Utah, United States.
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Asiaceratops (meaning "Asian horned face") is a genus of herbivorous ceratopsian dinosaur. It lived during the Late Cretaceous. Its fossils have mainly been found in Uzbekistan; a referred species is known from China and Mongolia.
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Ceratopsia or Ceratopia ( or ; Greek: "horned faces") is a group of herbivorous, beaked dinosaurs that thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7 million years ago.Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix. The last ceratopsian species, Triceratops prorsus, became extinct during the Cretaceous–Paleogene extinction event, .
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Avaceratops is a genus of small herbivorous ceratopsian dinosaurs which lived during the late Campanian during the Late Cretaceous Period in what are now the Northwest United States. Most fossils come from the Judith River Formation.
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No. 113. Craspedodon from the Late Cretaceous (Santonian) of Belgium may also be a ceratopsian, specifically a neoceratopsian closer to ceratopsoidea than protoceratopsidae. Possible leptoceratopsid remains have also been described from the early Campanian of Sweden.
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Agujaceratops (meaning "horned face from Aguja") is a genus of horned dinosaur from the Late Cretaceous (Campanian) of west Texas. It is a chasmosaurine (long-frilled) ceratopsian. Two species are known, Agujaceratops mariscalensis, and A. mavericus.
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Magnirostris lived in deserts with dunes. Other dinosaurs discovered in the Bayan Mandahu include Protoceratops helleninkorhinus, another primitive ceratopsian, and possibly Velociraptor osmolskae, a small predatory theropod.Paul, Gregory S. The Princeton Field Guide to Dinosaurs. 2nd ed.
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Xu Xing (; born 1969) is a Chinese paleontologist who has named more dinosaurs than any other living paleontologist. Such dinosaurs include the Jurassic ceratopsian Yinlong, the Jurassic tyrannosauroid Guanlong, the large oviraptorosaur Gigantoraptor, and the troodontid Mei.
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Mosaiceratops is a genus of ceratopsian described by Zheng, Jin & Xu in 2015 found in the Xiaguan Formation of Neixiang County. Although phylogenetic analysis have found it to be the most basal neoceratopsian, the authors noted that several features in the premaxilla and nasal bones are shared with the family Psittacosauridae, indicating that neoceratopsians evolved premaxillary teeth twice and that Psittacosauridae is not a primitive family as previously thought.Zheng, W., Jin, X., & Xu, X. (2015). A psittacosaurid-like basal neoceratopsian from the Upper Cretaceous of central China and its implications for basal ceratopsian evolution.
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Brachyceratops ('short horned face') is a dubious genus of ceratopsian dinosaur known only from partial juvenile specimens dating to the late Cretaceous Period of Montana, United States. Brachyceratops has historically been known from juvenile remains, with one specimen having since been re- classified as Rubeosaurus ovatus.Andrew T. McDonald & John R. Horner, (2010). "New Material of "Styracosaurus" ovatus from the Two Medicine Formation of Montana", In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, 656 pp.
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Morphometric analysis shows that centrosaurines differ from other ceratopsian groups in skull, snout, and frill shapes. There is evidence to suggest that male centrosaurines had an extended period of adolescence and sexual ornamention did not appear until adulthood.
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Ferrisaurus is a genus of leptoceratopsid ceratopsian dinosaur from the Sustut Basin (Tango Creek Formation) in British Columbia, Canada. The type and only species is Ferrisaurus sustutensis. It is the first non-avian dinosaur described from British Columbia.
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Ceratopsipes goldenensis is an ichnospecies of dinosaur footprint. It is represented by massive pes prints approaching in width. If undistorted, the tracks may represent an unusually large ceratopsian dinosaur that could have potentially been as large as 12 metres (39.4 feet).
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Monoclonius (meaning "single sprout") is a dubious genus of herbivorous ceratopsian dinosaur found in the Late Cretaceous layers of the Judith River Formation in Montana, United States, and the uppermost rock layers of the Dinosaur Park Formation in Alberta, Canada dated to between 75 and 74.6 million years ago. Monoclonius was named by Edward Drinker Cope in 1876. Later, much taxonomic confusion was caused by the discovery of Centrosaurus, a very similar genus of ceratopsian that is known from much better remains. Today, typical Monoclonius specimens are usually believed to be juveniles or subadults, in many cases of other genera such as Centrosaurus.
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Restoration of Centrosaurus apertus At the conclusion of their research program, Eberth, Brinkman and Barkas were unable to identify the bonebeds' ceratopsian remains to a rank more specific than the subfamily Centrosaurinae. Nevertheless, every single ceratopsian fossil that could be identified from the bonebeds had features closely resembling those of Centrosaurus apertus. They consequently felt confident that the bonebed was mostly composed of that species. The researchers found that the larger bones in each bonebeds tended to lie at the base of the stratum with fragments of bone becoming smaller and less concentrated at higher positions in the mudstone bed.
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Zuniceratops, the earliest-known ceratopsian with brow horns, was described in the late 1990s, and Yinlong, the first known Jurassic ceratopsian, in 2005. These new finds have been vital in illustrating the origins of horned dinosaurs in general, suggesting an Asian origin in the Jurassic, and the appearance of truly horned ceratopsians by the beginning of the late Cretaceous in North America. In phylogenetic taxonomy, the genus Triceratops has been used as a reference point in the definition of Dinosauria; dinosaurs have been designated as all descendants of the most recent common ancestor of Triceratops and Neornithes (i.e. modern birds).
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The Javkhlant Formation is a geological formation in Mongolia whose strata date back to the Late Cretaceous possibly Santonian to Campanian. Ceratopsian, ornithopod and theropod remains been found in the formation. A prominent fossilized therizinosauroid nesting site is also known from the formation.
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Ceratopsians, famous for Protoceratops, Triceratops and Styracosaurus illustrate the evolution of frilled and horned skulls. The frills evolved from the shelf common to all Marginocephalia. Ceratopsians are separated into basal ceratopsians, including the parrot- beaked Psittacosaurus, and neoceratopsians. Diversity of ceratopsian skulls.
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Rubeosaurus (meaning "bramble or thornbush lizard") is a genus of ceratopsian dinosaur which lived in what is now North America. Rubeosaurus fossils have been recovered from strata of the upper Two Medicine Formation of the Upper Cretaceous of Montana, dating to 74.6 million years ago.
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Zhao, X., Cheng, Z., Xu., X., and Makovicky, P. J. 2006. "A new ceratopsian from the Upper Jurassic Houcheng Formation of Hebei, China." Acta Geologica Sinica, 80 (4): 467–473 Full text. The fossils were found in the Houcheng Formation of Hebei Province, northeastern China.
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Serendipaceratops was originally described as a member of the Neoceratopsia and one of the earliest known ceratopsian dinosaurs, and the only one known from the southern hemisphere, with the possible exception of the dubious South American genus Notoceratops, which also may be another kind of ornithischian dinosaur. In addition to the holotype ulna, another supposed ceratopsian ulna was found at Dinosaur Cove, in south-west Victoria. It is a little younger at 106 million years old, having been found in the Eumeralla Formation. The scientists who first studied the ulnae said that they most closely resembled those of Leptoceratops, but subsequent studies have shown that this interpretation is likely incorrect.
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Cope originally classified Dysganus in Trachodontidae, a family of hadrosauroids now considered a junior synonym of the family Hadrosauridae. In 1901, Franz Nopcsa von Felső-Szilvás assigned Dysganus to the Ceratopsia, either by reading Cope's original descriptions of the genus, or by Cope in 1890 indirectly suggesting that Dysganus was a ceratopsian rather than a "trachodontid". Later in 1907, Hatcher et al. republished Cope's original descriptions of Dysganus in their entirety and deduced that the holotype of D. encaustus included teeth of hadrosaurids (then trachodontids), and the teeth of ceratopsidsCoombs, Walter P., and Peter M. Galton. “Dysganus, an Indeterminate Ceratopsian Dinosaur.” Journal of Paleontology, vol.
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It was named based on a partial left dentary from Alberta, Canada. Gryphoceratops represents the oldest known leptoceratopsid and probably the smallest adult- sized ceratopsian known from North America. Leptoceratopsids are known from Eastern North America by a partial maxilla dated to the early Campanian of North Carolina, whilst the European material referred to Leptoceratopsidae consists of isolated teeth and vertebrae from the early Campanian of Sweden. The former represents the first known ceratopsian from Eastern North America, and its specialised maxillary anatomy supports the hypothesis that Appalachia was isolated from Western Europe and Laramidia for an extended period during the Late Cretaceous, resulting in an endemic Late Cretaceous fauna.
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Zuniceratops ('Zuni-horned face') was a ceratopsian dinosaur from the mid Turonian of the Late Cretaceous Period of what is now New Mexico, United States. It lived about 10 million years earlier than the more familiar horned Ceratopsidae and provides an important window on their ancestry.
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Xu, X., Forster, C.A., Clark, J.M., and Mo, J. (2006). "A basal ceratopsian with transitional features from the Late Jurassic of northwestern China." Proceedings of the Royal Society B: Biological Sciences, 273(1598): 2135-2140. The known fossil material of Yinlong consists of many skeletons and skulls.
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Einiosaurus was a medium-sized herbivorous centrosaurine ceratopsian dinosaur from the Upper Cretaceous (Campanian stage) of northwestern Montana. The name means 'buffalo lizard', in a combination of Blackfeet Indian eini and Latinized Ancient Greek sauros; the specific name (procurvicornis) means 'with a forward-curving horn' in Latin.
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Cerasinops (meaning 'cherry face') was a small ceratopsian dinosaur. It lived during the Campanian of the late Cretaceous Period."Missing Link" Dinosaur Discovered in Montana, a National Geographic article; the photographed skeleton is actually from Montanoceratops. Its fossils have been found in Two Medicine Formation, in Montana.
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Platyceratops is a genus of ceratopsian dinosaur from the Late Cretaceous of Mongolia. It lived during the Campanian stage, about 75-72 million years ago. The name Platyceratops is derived from Greek, and means "flat horned face". Platyceratops is similar to Bagaceratops, although its skull is larger.
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Another formation with Tyrannosaurus remains is the Lance Formation of Wyoming. This has been interpreted as a bayou environment similar to today's Gulf Coast. The fauna was very similar to Hell Creek, but with Struthiomimus replacing its relative Ornithomimus. The small ceratopsian Leptoceratops also lived in the area.
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Kulceratops is a genus of ceratopsian dinosaur from the Early Cretaceous. It lived in the late Albian stage. It is one of the few ceratopsians known from this period. However, the fossils from this genus have been sparse: only jaw and tooth fragments have been found so far.
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Lamaceratops (meaning "Lama horned face"), is a ceratopsian dinosaur from the Late Cretaceous of Mongolia. It was discovered in the Khulsan locality in the Nemegt Valley, outer Mongolia. The validity of this species remains in doubt, as the fossils may in fact be referable to Bagaceratops.V. R. Alifanov. 2003.
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Montanoceratops is an extinct genus of small ceratopsian dinosaur that lived approximately 70 million years ago during the latter part of the Cretaceous Period in what is now Montana and Alberta. Montanoceratops was a small sized, moderately-built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated long.
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Dysganus (dis-GANN-us) (meaning "rough enamel") is a dubious genus of ceratopsian dinosaur from the Campanian stage of the Late Cretaceous. Its fossil teeth were discovered by Edward Drinker Cope in the Judith River Formation in Montana.E. D. Cope. 1876. Descriptions of some vertebrate remains from the Fort Union Beds of Montana.
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Asiaceratops, like all ceratopsians, was a 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 leaves or needles.
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Microceratus, like all ceratopsians, was a 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 leaves or needles.
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Andrew T. McDonald & John R. Horner, (2010). "New Material of "Styracosaurus" ovatus from the Two Medicine Formation of Montana". Pages 156–168 in: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, Bloomington and Indianapolis, IN.
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Prenoceratops, like all ceratopsians, was a 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 leaves or needles.
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Restoration Ischioceratops is one of the few ceratopsian dinosaurs which is not known by the skull. The most peculiar traits were located in the ischium, which shows a unique morphology. Another characteristic of Ischioceratops was the presence of a caudal elevation in its proximal part, which is present also in Protoceratops, Koreaceratops and in a more similar way in Montanoceratops and Cerasinops. The taxon has been referred to Leptoceratopsidae and distinguished from other known leptoceratopsids based on the following combination of characters: nine sacral vertebrae, more than in any other known basal (non-ceratopsid) ceratopsian but fewer than in ceratopsids; the ischium has a robust shaft that resembles that of a recurved bow and flares gradually to form a subrectangular-shaped obturator process in its middle portion.
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The pterosaur gives up as the ceratopsian herd arrives to cross the river. As they cross the river, groups of Prognathodon arrive and pull many of them underwater. Scar dives in while the mosasaurs continue their attack on the Pachyrhinosauruses. Scar eventually reaches the far bank and reunites with the Edmontosaurus herd, finally reaching safety.
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Utahceratops (meaning "Utah" κέρας (keras, "horn") and ὤψ (ōps, "face")) is an extinct genus of ceratopsian dinosaur that lived approximately 76.4~75.5 million years ago during the Late Cretaceous period in what is now Utah. Utahceratops was a large-sized, robustly-built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated long.
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Kulceratops, like all ceratopsians, was a herbivore. During the early 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 leaves or needles.
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Zhuchengceratops is a genus of extinct leptoceratopsid ceratopsian that lived during the Upper Cretaceous of modern-day China. It was first described in 2010, by Xu et al., who created the binomial Zhuchengceratops inexpectus. The name is derived from the location of Zhucheng, the Latinized-Greek ceratops, or "horned face", and the unexpected articulated nature of the holotype.
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Micropachycephalosaurus (meaning "small thick-headed lizard") is a monotypic genus of ceratopsian dinosaur. It lived in China during the Late Cretaceous period.Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix. The skeleton of the single specimen was found on a cliff southwest of Laiyang, Shandong Province.
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Ceratopsian fossil discoveries. The presence of Jurassic ceratopsians only in Asia indicates an Asian origin for the group, while the more derived ceratopsids occur only in North America save for one Asian species. Questionable remains are indicated with question marks. Ceratopsia appears to have originated in Asia, as all of the earliest members are found there.
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Michael W. Skrepnick is a Canadian palaeoartist best known for his illustrations of prehistoric animals. He has produced illustrations featured in natural history museums, scientific journals, books and magazines. He lives and works in Alberta, Canada. Skrepnick is noted for his acrylic paintings of dinosaurs, such as his rendition of the 2016 discovery of the ceratopsian dinosaur Spiclypeus shipporum.
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Auroraceratops, meaning "dawn horned face", is a genus of bipedal basal neoceratopsian dinosaur, from the Early Cretaceous (Aptian age) of north central China and South Korea. The etymology of the generic name refers to its status as an early ceratopsian and also to Dawn Dodson, wife of Peter Dodson, one of the palaeontologists who described it.
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Reconstructed skeleton of Utahceratops with known elements in yellow Selected craniofacial elements Size comparison Utahceratops has been classified as a basal chasmosaurine ceratopsian. It has been found to be in a clade of basal chasmosaurines with Pentaceratops. The below cladogram follows Longrich (2014), who named a new species of Pentaceratops, and included nearly all chasmosaurine species.
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These two group classifications separated the species population in half, which is highly indicative of sexual dimorphism. However, some report that the two groups may actually represent two separate species. Protoceratops, a type of ceratopsian, also shows signs of sexual dimorphism. However, their frills don't seem to develop until later in life, and may be coordinated with sexual maturity.
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They join the sauropod convoy, but are attacked by a pack of Tyrannosaurus and Allosaurus, during which Crabb escapes in his strutter and the head of the ceratopsian strutter is ripped off. But the controls remain undamaged. However, afterward, it still works properly (and can be driven and controlled) without a head. But it behaves strangely.
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Its helmet bears the signature unicorn- like single horn, and a 'frill', giving an appearance reminiscent of a ceratopsian dinosaur. The horn and the glowing eyes also gives the Evangelion a rather demonic appearance. It also has a distinctive chest plate resembling pectoral muscles, as opposed to the regular V-shaped chest plate the other Evangelions have.
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Magnirostris, from the Latin magnus "large" and rostrum "beak", is the name given to a genus of dinosaur from the upper Campanian stage in the Upper Cretaceous. It was a ceratopsian which lived in Inner Mongolia in China. It is distinguished from other protoceratopsids by its large beak (hence the name) and incipient orbital horn cores.
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Restoration of a resting individual Turanoceratops, like all ceratopsians, was a 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 and conifers. It would have used its sharp ceratopsian beak to bite off the leaves or needles.
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Just like the Claosaurus specimen, it is possible that the specimens of Niobrarasaurus, Silvisaurus and Hierosaurus floated into the Interior Seaway from the east, since these two species of nodosaurids were discovered in the famous chalk formations of Kansas and are not known from any location from Western North America. Kansas was also a part of Appalachia when the other parts were covered by oceans, which were a part of the Western Interior Seaway. While remains of the advanced ceratopsians, most notably the centrosaurines and chasmosaurines which were very common in Laramidia during this time period, where not found in Appalachia, the leptoceratopsids somehow managed to inhabit that location. A Campanian-era leptoceratopsid ceratopsian has been found in the Tar Heel Formation, marking the first discovery of a ceratopsian dinosaur in the Appalachian zone.
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C.W. Gilmore, 1917, "Brachyceratops, a ceratopsian dinosaur from the Two Medicine Formation of Montana, with notes on associated fossil reptiles", United States Geological Survey Professional Paper 103: 1-45 In 1939 Gilmore referred a larger subadult specimen, USNM 14765, to Brachyceratops.Gilmore C.W. 1939, "Ceratopsian dinosaurs from the Two Medicine Formation, Upper Cretaceous of Montana", Proceedings of the United States National Museum 87: 1–18 All specimens are currently part of the collection of the Smithsonian Institution in Washington D.C., where a skeletal restoration is mounted. As Brachyceratops is known only from the remains of five juveniles — plus the subadult that Gilmore found about a mile from the original specimens —, it was long considered likely that these represented the immature forms of known centrosaurine ceratopsians, with Monoclonius often suggested as the likeliest candidate.
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Liaoceratops, meaning "Liaoning horned face", is a ceratopsian dinosaur believed to be an early relative of the horned ceratopsids. It lived in the Early Cretaceous, 126 million years ago. It was discovered in China by a team of American and Chinese scientists. Liaoceratops was much smaller than its later relatives, but offers a glimpse into the early evolution of this group of dinosaurs.
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Avaceratops, like all ceratopsians, was a herbivore. During the Cretaceous, flowering plants were "geographically limited on the landscape", 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 leaves or needles. The habitat of Avaceratops was heavily forested and wet.
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In theropod dinosaurs, the antorbital fenestra is the largest opening in the skull. Systematically, the presence of the antorbital fenestra is considered a synapomorphy that unites tetanuran theropods as a clade. In contrast, most ornithischian dinosaurs reduce and even close their antorbital fenestrae such as in hadrosaurs and the dinosaur genus Protoceratops. This closure distinguishes Protoceratops from other ceratopsian dinosaurs.
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Chaoyangsauridae is a family of ceratopsian dinosaurs. They are among the earliest known marginocephalian dinosaurs, with remains dating to about 160 million years ago, during the Late Jurassic period. Members of this group had sharp beaks for snipping off leaves to eat, and a very small frill. Four dinosaur genera, Chaoyangsaurus, Xuanhuaceratops, Yinlong and Hualianceratops, are usually considered to belong to the Chaoyangsauridae.
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Yamaceratops is a genus of dinosaur from the Late Cretaceous. It was a primitive ceratopsian which lived in the Gobi Desert of Mongolia. Initially, the rocks it was found in were thought to be from the Early Cretaceous, but the age was reevaluated in 2009. The type species, Yamaceratops dorngobiensis, was described by P. J. Makovicky and M. A. Norell in September, 2006.
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Skin impressions were also uncovered beneath the skeleton and evidence from the matrix that it was buried in indicated that the juvenile ceratopsian drowned during a possible river crossing. Further study of the specimen revealed that juvenile chasmosaurs had a frill that was narrower in the back than that of adults, as well as being proportionately shorter in relation to the skull.
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Chasmosaurus ( ) is a genus of ceratopsid dinosaur from the Upper Cretaceous Period of North America. Its name means 'opening lizard', referring to the large openings (fenestrae) in its frill (Greek chasma meaning 'opening' or 'hollow' or 'gulf' and sauros meaning 'lizard'). With a length of and a weight of , Chasmosaurus was a ceratopsian of average size. Like all ceratopsians, it was purely herbivorous.
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Leptoceratops (meaning 'little-horned face' and derived from Greek lepto-/λεπτο- meaning 'small', 'insignificant', 'slender', 'meagre' or 'lean', kerat-/κερατ- meaning 'horn' and -ops/ωψ meaning face), is a genus of primitive ceratopsian dinosaurs from the late Cretaceous Period (late Maastrichtian age, 66.8-66 Ma ago) of what is now Western North America. Their skulls have been found in Alberta, Canada and Wyoming.
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He has set up an annual ceratopsian (horned dinosaur) research scholarship for University-level students or academics under the Dinosaur Research Institute in Calgary, with whom he is on the board of Directors (beginning in 2008). $1500.00 CDN is awarded each year, the winner notified in May. His current lab work involves the preparation of a hadrosaur skull from near Maycroft, Alberta.
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Chris Beard, Hunt for the Dawn Monkey, p. 307 Mrs. Yvette Borup Andrews, first wife of Roy Chapman Andrews, feeding Tibetan Bear cub in 1917 On July 13, 1923, the party was the first in the world to discover dinosaur eggs. Initially thought to be eggs of a ceratopsian, Protoceratops, they were determined in 1995 actually to belong to the theropod Oviraptor.
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Attributes of the ceratopsian dinosaur Torosaurus, and new material from the Javelina Formation (Maastrichtian) of Texas. Journal of Paleontology 82(6): 1127–1138. Scanella and Horner concluded that only future finds could solve this problem. They suggested that this taxon, which extends the Torosaurus range southwards of that of Triceratops, might represent a separate chasmosaurine genus or a third Triceratops species.
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Nasutoceratops is an extinct genus of ceratopsian dinosaur. It is a basal centrosaurine which lived during the Late Cretaceous Period (late Campanian, about 76.0-75.5 Ma). Fossils have been found in southern Utah, United States. Nasutoceratops was a large, ground-dwelling, quadrupedal herbivore with a short snout and unique rounded horns above its eyes that have been likened to those of modern cattle.
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The results of pioneering efforts to age dinosaur fossils using growth ring counts suggest that the longevity of the basal ceratopsian Psittacosaurus mongoliensis was 10 or 11 years.Erickson, G. M. and Tumanova, T. A. (2000). Growth curve and life history attributes of Psittacosaurus mongoliensis (Ceratopsia: Psittacosauridae) inferred from long bone histology. Zoological Journal of the Linnean Society. 130:551-566.
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"Magulodon" is the name given to an as yet undescribed genus of dinosaur from the Early Cretaceous (Aptian to Albian stages, approximately 112 million years ago). It was a possible ornithischian, either an ornithopod or basal ceratopsian, which lived in what is now Maryland, in the United States. The type species, "Magulodon muirkirkensis", was coined by Kranz in 1996.Kranz, P. (1996).
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Christopher J. Ott and Peter L. Larson, 2010, "A New, Small Ceratopsian Dinosaur from the Latest Cretaceous Hell Creek Formation, Northwest South Dakota, United States: A Preliminary Description", In: Ryan, M.J., Chinnery-Allgeier, B.J., and Eberth, D.A. (eds.) New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Bloomington, Indiana University Press, 656 pp. Tatankaceratops is known from one specimen housed at the Black Hills Institute, BHI 6226. In 2011, Nick Longrich published a paper containing a brief re-evaluation of Tatankaceratops. Longrich suggested that Tatankaceratops appeared to possess a bizarre mix of characteristics from adult and juvenile Triceratops specimens; the animal's small size and short, slender brow horns are consistent with the animal being a juvenile, but the gnarled bone and fusion of skull elements to one another are typical of old adult ceratopsians.
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In Protoceratops and Bagaceratops (and also in the non-protoceratopsid Leptoceratops), there is a blade-shaped parietal sagittal crest (Sereno 2000: 505). Several other more recently recognized genera may also be protoceratopsids. In 2003, Vladimir Alifanov named, but did not define, a new ceratopsian family Bagaceratopidae to include Bagaceratops, Platyceratops, Lamaceratops and Breviceratops. However, applying Sereno's phylogenetic definition, Alifanov's Bagaceratopidae appears to be a subclade of Protoceratopsidae.
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Sinoceratops is an extinct genus of ceratopsian dinosaur that lived approximately 73 million years ago during the latter part of the Cretaceous Period in what is now Shandong province in China. It was named in 2010 by Xu Xing et al. for three skulls from Zhucheng, China. The name of its type species Sinoceratops zhuchengensis means "Chinese horned face from Zhucheng", after the location of its discovery.
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Therizinosaurs such as Falcarius are also known from the Early Cretaceous of North America. Finally, during the Late Cretaceous Period, the greatest abundance and diversity of dinosaurs of all time lived in North America. During the early part of the Late Cretaceous, the therizinosaur Nothronychus and the ceratopsian Zuniceratops lived. During the Campanian stage of the Late Cretaceous, an enormous diversity of dinosaurs is known.
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Gobiceratops (meaning "Gobi horned face") is a genus of ceratopsian dinosaur from the Upper Cretaceous of Mongolia. It is based on a skull that is long, from the Khermin Tsav locality in the Barun Goyot Formation of southern Mongolia; the type individual was young. Gobiceratops is thought to have been related to Bagaceratops, and a member of Bagaceratopidae. It was described in 2008 by Alifanov.
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Throughout the rest of the century, paleontologists would be occupied with several controversies regarding ceratopsian paleobiology. One concerned the stance of the ceratopsid forelimbs. When Marsh first reconstructed the ceratopsid forelimb, he portrayed it in an erect posture. However, when later researchers like Sternberg and Osborn tried to mount the skeletons, they found that the forelimb bones apparently sprawled despite the hindlimbs standing straight up and down.
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Turanoceratops ("Turan horned face") is a genus of herbivorous ceratopsian dinosaur from the late Cretaceous Bissekty Formation of Uzbekistan. The fossils dated from the mid-late Turonian stage, roughly 90 million years ago. The skull bore a pair of long brow horns like those seen in the Ceratopsidae, although Turanoceratops appears to have been transitional between earlier ceratopsians and ceratopsids, and not a ceratopsid itself.
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Sampson also named "Taxon B" as the genus Einiosaurus in the same article wherein Achelousaurus was described. He said paleontologists needed to be cautious when naming new ceratopsian genera because their intraspecific variation (i.e., variation within a species) might be mistaken for interspecific differences (between species). Until 1995, only one new genus of centrosaurine dinosaur had been named since Pachyrhinosaurus in 1950, namely Avaceratops in 1986.
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They discovered it to be a new species and genus, and it was described in 2012 by Ryan, Evans, and Kieran M. Shepherd. At the time of discovery, Xenoceratops foremostensis was the oldest known taxon of ceratopsid dinosaur in Canada. It is also the first ceratopsian described from the Foremost Formation. Xenoceratops is named from the Greek xenos, meaning foreign or alien, and ceratops, meaning horned face.
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The skeleton was found in the Wangshi Group, which is of Late Cretaceous age, and most fossils are only disarticulated bones of Shantungosaurus. Zhuchengceratops shares may features with Leptoceratopsidae as well as other ceratopsian groups such as Ceratopsidae. The overall size of the taxon was similar to Leptoceratops, although slightly larger. Zhuchengceratops was analyzed to be in a group with Leptoceratops and Udanoceratops, although internal relationships of this triplet were unresolved.
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Fiorelli, L. E. and Calvo, J. O. (2007). The first “protosuchian” (Archosauria: Crocodyliformes) from the Cretaceous (Santonian) of Gondwana. Arquivos do Museu Nacional, Rio de Janeiro 65(4):417-459. The localities from which specimens of this genus have been found have also yielded many other vertebrate remains such as those of palaeonisciform fishes, turtles, various lizards, troodontids, triconodonts, the ceratopsian Psittacosaurus, and the protosuchian-grade crocodylomorph Tagarosuchus.
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The area was most likely an estuarine environment, judging from fossils found there. Dinosaurs were part of the state's fauna at the time. In fact, this unit is the primary source of the state's dinosaur fossils. Dinosaurs found in the state include the ornithomimid Coelosaurus antiquus, the hadrosaurids Hypsibema crassicauda and (possibly) Hadrosaurus, an indeterminate tyrannosauroid (possibly Dryptosaurus), and an unidentified leptoceratopsid (the first ceratopsian known from the East Coast).
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The Masuk consists of cliff-forming cross-bedded sandstones and slope-forming yellowish-gray to bluish-gray mudstones with interbedded light gray sandstones. Fossils of bivalves, ceratopsian dinosaurs, crocodiles, gastropods, and turtles have been collected in this member.Morris et al., 2003, page 95, "Mancos Shale" The Western Interior Seaway was shrinking due to infilling and uplift while the high mountains to the east were being reduced by erosion.
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Reconstructed skull Zuniceratops is an example of the evolutionary transition between early ceratopsians and the later, larger ceratopsids that had very large horns and frills. This supports the theory that the lineage of ceratopsian dinosaurs may have been North American in origin. Although the first specimen discovered had single-rooted teeth (unusual for ceratopsians), later fossils had double-rooted teeth. This is evidence that the teeth became double-rooted with age.
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Restoration of Daspletosaurus feeding on a ceratopsian In the late Campanian of North America, Daspletosaurus was a contemporary of the albertosaurine tyrannosaurid Gorgosaurus. This is one of the few examples of two tyrannosaur genera coexisting. In modern predator guilds, similar-sized predators are separated into different ecological niches by anatomical, behavioral or geographical differences that limit competition. Several studies have attempted to explain niche differentiation in Daspletosaurus and Gorgosaurus.
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Psittacosaurus ( ; "parrot lizard") is a genus of extinct ceratopsian dinosaur from the Early Cretaceous of what is now Asia, existing between 126 and 101 million years ago. It is notable for being the most species-rich dinosaur genus. Up to 12 species are known, from across China, Mongolia, Siberia, and possibly Thailand and Laos. The species of Psittacosaurus were obligate bipeds at adulthood, with a high skull and a robust beak.
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L.A. Nessov, L F. Kaznyshkina, and G.O. Cherepanov. 1989. [Mesozoic ceratopsian dinosaurs and crocodiles of central Asia]. In: Bogdanova and Khozatskii (eds.), Theoretical and Applied Aspects of Modern Palaeontology pp 144-154 The holotype of Asiaceratops salsopaludalis, CCMGE 9/12457, was found in Uzbekistan in a layer of the Khodzhakul Formation dating from the early Cenomanian, about ninety-nine million years old. It consists of a part of a left maxilla.
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Skull The first small ceratopsian named Leptoceratops was discovered in 1910 by Barnum Brown in the Red Deer Valley in Alberta, Canada. He described it four years later. The first specimen had a part of its skull missing, but there were later well-preserved finds by C. M. Sternberg in 1947, including one complete fossil. Later material was found in 1978 in the Bighorn Basin of northern Wyoming.
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Restoration Diabloceratops was built like a typical ceratopsian in that it had a large neck frill made of bone. It had a small horn on the nose, perhaps a second horn in front of that, and a pair of relatively small horns above the eyes. The skull is deeper and shorter than that of any other centrosaurines. Upon the frill it also had a pair of very long spikes as in Einiosaurus and Styracosaurus.
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Dicynodont fossils Diictodon. Life-sized model The dicynodont skull is highly specialised, light but strong, with the synapsid temporal openings at the rear of the skull greatly enlarged to accommodate larger jaw muscles. The front of the skull and the lower jaw are generally narrow and, in all but a number of primitive forms, toothless. Instead, the front of the mouth is equipped with a horny beak, as in turtles and ceratopsian dinosaurs.
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Armour, although all used for the sole intent to ward off attackers, can be split into defensive and offensive armour. Examples of offensive armour are horns, hooves, antlers, claws and beaks, clubs and pincers, as developed in some mammals, birds, reptiles (including dinosaurs, such as the dromaeosaurid claw and the ceratopsian horn) and arthropods. Offensive armour is often used in conjunction with defensive armour and in some cases makes an animal almost unassailable.
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Agathaumas (; "great wonder") is a dubious genus of a large ceratopsid dinosaur that lived in Wyoming during the Late Cretaceous (late Maastrichtian stage, 66 million years ago). The name comes from the Greek – "much" – and – "wonder". It is estimated to have been long and weighed , and was seen as the largest land animal known at the time of its discovery. It was the first named ceratopsian, though relatively little is known about it.
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Soon after its description, a controversy arose over the stegosaur's name, which is very similar to the ceratopsian Centrosaurus. Under the rules of biological nomenclature, forbidding homonymy, two animals may not be given the same name. Hennig renamed his stegosaur Kentrurosaurus, "pointed-tail saurian", in 1916, while Hungarian paleontologist Franz Nopcsa renamed the genus Doryphorosaurus, "lance-bearing saurian", the same year. If a renaming had been necessary, Hennig's would have had priority.
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The early 20th century was a fruitful time for ceratopsian research. In 1907, Hatcher and others published a monograph on ceratopsid anatomy that is still considered the single most significant publication on the topic to date. Many new species were being described, including Centrosaurus, Styracosaurus, and Chasmosaurus. Not long after, the Central Asiatic Expedition led by Roy Chapman Andrews of the American Museum of Natural History discovered the primitive ceratopsians Psittacosaurus and Protoceratops in Mongolia.
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However, further study showed these remains to come from a different centrosaurine, Medusaceratops. Both ceratopsids lived during the same time period, about 77.5 million years ago.Ryan, Michael J.; Russell, Anthony P., and Hartman, Scott. (2010). "A New Chasmosaurine Ceratopsid from the Judith River Formation, Montana", In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, 656 pp. .
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F) & G) Triceratops side & top. H) & I) Styracosaurus side (without lower jaw) & top. The evolution of ceratopsid dinosaurs shares characteristics with the evolution of some mammal groups, both were "geologically brief" events precipitating the simultaneous evolution of large body size, derived feeding structures, and "varied hornlike organs." The sequence of ceratopsian evolution in the Cretaceous is roughly from Psittacosaurus (121 -99 Ma) to Protoceratops (83 Ma) to (Triceratops 67 Ma and Styracosaurus 72 Ma).
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This is presumed to have been useful for breaking down tough vegetation through bacterial fermentation. Another adaptation for advanced vegetation digestion is seen in Ceratopsians, which evolved features to improve their chewing apparatus. Derived ceratopsians have vertical grinding surfaces on their teeth to maximize break-down of tough vegetation. There is also evidence of advanced adductor musculature that extends from a large coronoid process on the mandible up to the ceratopsian frill, which would increase chewing force.
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It shared its paleoenvironment with other dinosaurs, such as the hadrosaurs Acristavus and Adelolophus, the ceratopsian Diabloceratops, and unnamed ankylosaurs and pachycephalosaurs. Vertebrates present in the Wahweap Formation at the time included freshwater fish, bowfins, abundant rays and sharks, turtles such as Compsemys, crocodilians, and lungfish. Numerous mammals lived in this region, which included several genera of multituberculates, cladotherians, marsupials, and placental insectivores. The mammals were more primitive than those that lived in the younger Kaiparowits Formation.
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Sinankylosaurus is known from the Xingezhuang Formation of southern China. It is known from a single ilium. Alongside it, in the formation, lived Sinoceratops, a ceratopsian, Shantungosaurus, a very common hadrosaurid to which most of the material has been assigned, Zhuchengtyrannus, an Asian tyrannosaurid related to Tarbosaurus, Zhuchengceratops, an Asian leptoceratopsid, and Huaxiaosaurus, a possible older individual of Shantungosaurus. Other possible remains have been assigned to Zhuchengosaurus, a probable junior synonym of Shantungosaurus, and material tentatively assigned to Tyrannosaurus.
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Hence the genus name, referring to serendipity and combining this reference with ~ceratops, a common suffix in ceratopsian generic names. The specific name honours science fiction writer Arthur C. Clarke. A personal friend of the couple and author of books such as 2001: A Space Odyssey and Rendezvous with Rama, Clarke first became interested in science as a child because he became fascinated by dinosaurs. Perhaps coincidentally, "Serendip" is a former name for Sri Lanka, Clarke's adoptive country.
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Life reconstruction of Y. downsi Yinlong was a relatively small dinosaur, with a total length of about from nose to tail, and a weight of about . Long robust hindlimbs and shorter slender forelimbs with three-fingered hands suggests a bipedal lifestyle like many small ornithopods. Despite a virtually frill-less and totally hornless skull, Yinlong is a ceratopsian. Its skull is deep and wide and relatively large compared to most ornithischians, but also proportionately smaller than most other ceratopsians.
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Ceratops (meaning "horn face") is a dubious genus of herbivorous ceratopsian dinosaur which lived during the Late Cretaceous. Its fossils have been found in the Judith River Formation in Montana. Although poorly known, Ceratops is important in the history of dinosaurs, since it is the type genus for which both the Ceratopsia and the Ceratopsidae have been named. The material is too poor to be confidently referred to better specimens, and Ceratops is thus considered a nomen dubium.
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It was not until 1999 that the dinosaur finally received an official name. Sereno (1999) used the name Chaoyangsaurus in an overview of ceratopsian taxonomy. Once again, that name was a nomen nudum. However, in December of that year, Cheng, Zhao, and Xu published an official description using the name Chaoyangsaurus youngi, and as the first name for this genus that is not a nomen nudum, it has official priority over all other spellings that have been used.
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The first two genera would be transitional forms, evolving through anagenesis from Styracosaurus. There has been debate about this theory, with later discoveries showing that Achelousaurus is closely related to Pachyrhinosaurus in the group Pachyrhinosaurini. Achelousaurus is known from the Two Medicine Formation and lived in the island continent of Laramidia. As a ceratopsian, Achelousaurus would have been a herbivore and it appears to have had a high metabolic rate, though lower than that of modern mammals and birds.
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There is currently disagreement about the function of the enlarged "sickle claw" on the second toe. When John Ostrom described it for Deinonychus in 1969, he interpreted the claw as a blade-like slashing weapon, much like the canines of some saber-toothed cats, used with powerful kicks to cut into prey. Adams (1987) suggested that the talon was used to disembowel large ceratopsian dinosaurs. The interpretation of the sickle claw as a killing weapon applied to all dromaeosaurids.
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Stenopelix (meaning "narrow pelvis") is a genus of small marginocephalian dinosaur, possibly a basal ceratopsian, from the Early Cretaceous of Germany. It lived in the late Berriasian Stage of the Cretaceous period, approximately 140 myr ago.Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to- Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix. The genus is based on a partial skeleton lacking the skull, and its classification is based on characteristics of the hips.
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Craspedodon (meaning 'edge tooth') is an extinct genus of ornithischian dinosaur, possibly a ceratopsian. It lived during the Late Cretaceous (Santonian stage, around 85 million years ago), in what is now Belgium. Only a few teeth have ever been found, which were described as similar to those of Iguanodon. Craspedodon lonzeensis, described by Louis Dollo in 1883, is the type species, although it is considered a nomen dubium since it is based on fragmentary material (teeth only).
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Fossil skull and mandible Zhuchengceratops is a derived leptoceratopsid ceratopsian which lived during the Late Cretaceous period in what is now Kugou, Zhucheng County, China. It is known from a partial articulated skeleton including vertebrae, ribs, teeth, and parts of the skull and mandibles. The fossils were recovered from the Wangshi Group, of the Late Cretaceous. This genus was named by Xing Xu, Kebai Wang, Xijin Zhao, Corwin Sullivan and Shuqing Chen in 2010, and the type species is Zhuchengceratops inexpectus.
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The genus name was chosen for the location of Zhucheng, where the holotype was found, and the Latinized-Greek ceraptops, meaning "horned face". They chose the species name inexpectus to refer to the unexpected discovery of the articulated skeleton. The recovered specimen of Zhuchengceratops likely represents an adult, and is slightly larger than most adults of the similar ceratopsian Leptoceratops, which was around 2 meters in length. Zhuchengceratops had a particularly massive and deep 50 cm-long mandible that is also thin transversely.
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While the Cretaceous is often referred to as the end of the age of dinosaurs, many new lifeforms appeared. This is the age of Tyrannosaurus rex and the ceratopsian dinosaurs (armoured and horned dinosaurs like Triceratops). The abundant marine deposits of the North East coast of South Africa are of this age. There is also the hope of finding the rarest forms of vertebrates alive in this time period – the tiny mammals which would eventually dominate the planet after the Cretaceous extinction event.
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Ironically, the diminutive Liaoceratops may also help scientists understand the roles of horns and frills in ceratopsian dinosaurs. First thought of as offensive or defensive organs, these structures are seen by many paleontologists today as display devices used in species recognition and to attract mates. Liaoceratops has a small jugal horn facing sideways under and behind each of its eyes. As this structure is relatively small and light, Makovicky believed that it was a display organ and had no purpose in defense.
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An early ceratopsian: Psittacosaurus Montanoceratops, a leptoceratopsid A typical protoceratopsid: Protoceratops skeleton at the Wyoming Dinosaur Center Styracosaurus, a centrosaurine ceratopsid Triceratops, one of the largest ceratopsians (a chasmosaurinae ceratopsid). It had solid frill and long horns. Following Marsh, Ceratopsia has usually been classified as a suborder within the order Ornithischia. While ranked taxonomy has largely fallen out of favor among dinosaur paleontologists, some researchers have continued to employ such a classification, though sources have differed on what its rank should be.
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Not much is known about Angonisaurus that distinguishes it functionally different from other herbivorous dicynodont relatives. The dicynodont skull is highly specialised, light but strong, with the synapsid temporal openings at the rear of the skull greatly enlarged to accommodate larger jaw muscles. The front of the skull and the lower jaw are generally narrow and, in all but a number of primitive forms, toothless. Instead, the front of the mouth is equipped with a horny beak, as in turtles and ceratopsian dinosaurs.
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A large centrosaurine, Achelousaurus was about long, with a weight of about . As a ceratopsian, it walked on all fours, had a short tail and a large head with a hooked beak. It had a bony neck-frill at the rear of the skull, which sported a pair of long spikes, which curved towards the outside. Adult Achelousaurus had rough bosses (roundish protuberances) above the eyes and on the snout where other centrosaurines often had horns in the same positions.
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Close-up of the AM5372 skull, American Museum of Natural History The large nasal horns and frills of Styracosaurus are among the most distinctive facial adornments of all dinosaurs. Their function has been the subject of debate since the first horned dinosaurs were discovered. Early in the 20th century, paleontologist R. S. Lull proposed that the frills of ceratopsian dinosaurs acted as anchor points for their jaw muscles. He later noted that for Styracosaurus, the spikes would have given it a formidable appearance.
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Therizinosaurs were the most abundant theropods in the Bayan Shireh Formation in terms of biodiversity; in addition to Segnosaurus, members of the group included Erlikosaurus, Enigmosaurus, and possibly a fourth type. Other theropods included the tyrannosaur Alectrosaurus, the ornithomimid Garudimimus, and the dromaeosaur Achillobator. Other dinosaurs included the ankylosaur Talarurus, the hadrosaur Gobihadros, the sauropod Erketu, and the ceratopsian Graciliceratops. Dinosaur eggs, some of which were identified as Dendroolithidae, as well as footprints of dinosaurs and crocodyliforms, have also been found.
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Most of the bones were angled parallel to the plane of the bed. The researchers only found associated or articulated fossils at two of Hilda's bone beds; H97-03 had a partial Centrosaurus skull and H97-19 had a partial ceratopsian tail. As such, they regarded such higher quality specimens as very rare. Eberth, Brinkman, and Barkas tried to estimate the number of bones in the mega-bonebed in order to infer the number of animals that died together during the formation of the deposit.
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Ojoceratops ( meaning "Ojo Alamo horned face") is a genus of ceratopsian dinosaur which lived in what is now New Mexico, United States. Ojoceratops fossils have been recovered from strata of the Ojo Alamo Formation (Naashoibito Member), dating to the late Cretaceous period (probably Maastrichtian age, 68 million years agoSullivan, R.M., and Lucas, S.G. 2006. "The Kirtlandian land-vertebrate "age" – faunal composition, temporal position and biostratigraphic correlation in the nonmarine Upper Cretaceous of western North America." New Mexico Museum of Natural History and Science, Bulletin 35:7-29.).
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Ajkaceratops (pronounced "oi-ka-sera-tops") is a genus of ceratopsian dinosaur was described in 2010. It lived during the Late Cretaceous in what is now Europe, in what was then the western Tethyan archipelago. The type species, A. kozmai, is most closely related to forms in east Asia, from where its ancestors may have migrated by island-hopping. The generic name, Ajkaceratops, honors Ajka, a town in Hungary near Iharkút, where the fossils were discovered, combined with the Greek ceratops, meaning "horned face".
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Restoration of Agujaceratops mariscalensis Size comparison of Agujaceratops mariscalensis to a human Juvenile Agujaceratops skeleton as reproduced by Triebold Paleontology in Woodland Park, Colorado, USA In 1938, three dinosaur bone beds were excavated, and ceratopsian material was collected from Big Bend National Park (Texas) by William Strain. This material was studied by Lehman in 1989 and named Chasmosaurus mariscalensis. It is known only from the holotype UTEP P.37.7.086 a partial adult skull which includes a braincase, left supraorbital horncore, left maxilla and a right dentary.
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Later researchers like Robert T. Bakker and Gregory S. Paul attempted to revive the erect reconstruction, but continuing research in the 1990s by researchers like John Ostrom, Peter Dodson, and James Farlow found an intermediate value to be better supported. The original use of the ceratopsids' horns and frills was another long-running controversy in ceratopsian paleontology. Early researchers like Richard Swann Lull thought that bony frills served as the attachment site for enlarged jaw muscles. This explanation was followed by researchers like Russell, Haas, and Ostrom.
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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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A specimen of Centrosaurus apertus recovered from Dinosaur Provincial Park in 1989 was discovered to have crippling osteosarcoma in its right fibula. Examination of the cancerous lesions in the bone suggest the cancer had reached an aggressive stage. The cancer would have resulted in a severe limp that would have made the ceratopsian more vulnerable to predation. However, the fact that it was part of a herd allowed the Centrosaurus to survive much longer than would be expected for an animal infected with such severe disease.
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The Tyrrell Museum has also collected several partial Styracosaurus skulls. At least one confirmed bonebed (bonebed 42) in Dinosaur Provincial Park has also been explored (other proposed Styracosaurus bonebeds instead have fossils from a mix of animals, and nondiagnostic ceratopsian remains). Bonebed 42 is known to contain numerous pieces of skulls such as horncores, jaws and frill pieces. Holotype frill of S. ovatus, which was moved to Rubeosaurus A third species, S. ovatus, from the Two Medicine Formation of Montana, was described by Gilmore in 1930.
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The museum houses the Carthage Institute of Paleontology. The institute conducts field explorations with students from Carthage College and volunteers on Bureau of Land Management (BLM) land in the Late Cretaceous Hell Creek Formation. Fossils collected are kept at the museum and cleaned in the prep lab, as it is a federal repository. During the 2006 season, they discovered the remains of the youngest known Tyrannosaurus rex, nicknamed "Little Clint", with more bones of Little Clint found in 2007, along with hadrosaur and ceratopsian bones.
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Over the last 25 years he has worked on fossil discovery in Mongolia, Argentina, Antarctica, Dinosaur Provincial Park, Dry Island Buffalo Jump Provincial Park, and many other locations. His contributions to palaeontology include synonymising the genera Troodon and Stenonychosaurus in 1987 (with the former name taking precedence) and later reversing this in 2017. He has also synonymised the ceratopsian taxon Rubeosaurus with Styracosaurus, the latter being the valid, senior synonym. One of Currie's main interests has been the evolutionary link between modern birds and non-avian dinosaurs.
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The eggs of Citipati are the largest known definitive oviraptorid eggs, at 18 cm. In contrast, eggs associated with Oviraptor are only up to 14 cm long. C. osmolskae egg with preserved embryo Ironically, it was the association with eggs that gave oviraptorids their name (which means 'egg thieves'). The first oviraptorid eggs (of the genus Oviraptor) were found in close proximity to the remains of the ceratopsian dinosaur Protoceratops and it was assumed that the oviraptorids were preying upon the eggs of the ceratopsians.
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This left M. crassus, which he considered non- diagnostic, largely due to its damage and the lack of a nasal horn. Lambe ended the paper by referring Brown's M. flexus to Centrosaurus apertus, the type species of Centrosaurus. The next round fell in 1917 to Brown in a paper on Albertan centrosaurines, which, for the first time, analyzed a complete ceratopsian skeleton, specimen AMNH 5351 found by him in 1914, which he named Monoclonius nasicornus ("with the nose-horn"). In the same paper he described yet another species, Monoclonius cutleri, the epithet honouring William Edmund Cutler, based on specimen AMNH 5427, a headless skeleton featuring skin impressions. The matter bounced back and forth, over the next few years, until R.S. Lull published his "Revision of the Ceratopsia", in 1933. Although, unlike the 1907 monograph, it has relatively few illustrations, it attempted to identify and locate all ceratopsian specimens then known. Lull described another almost complete specimen from Alberta: AMNH 5341, presently exhibited as YPM 2015 at Yale's Peabody Museum in an unusual way: the left half shows the skeleton, but the right side is a reconstruction of the living animal, and referred it to a Monoclonius (Centrosaurus) flexus.
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The remains were collected in 2011 from Locality 7 of the Zhumapu Formation, as a part of a project to find dinosaurs for the Shanxi Museum of Geology, initiated by the Department of Land and Resources of Shanxi Province. SXMG V 00001 was found in the vicinity of Zuoyun County, from the lower part of Zhumapu Formation, dating to the early Late Cretaceous based on biostratigraphic correlations, overlying the late Early Cretaceous Zuoyun Formation. Other than SXMG V 00001, ankylosaur and ceratopsian remains were found from the newly discovered localities.
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Strongylocentrotus purpuratus, a well-armoured sea urchin Armour is evident on numerous animal species from both current and prehistoric times. Dinosaurs such as Ankylosaurus, as well as other Thyreophora (armoured dinosaurs such as Ankylosauria and Stegosauria), grew thick plate-like armour on their bodies as well as offensive armour appendages such as the thagomizer or a club. The armour took many forms, including osteoderms, spikes, horns, and plates. Other dinosaurs such as ceratopsian dinosaurs as well as some sauropods such as Saltasaurus, grew armour to defend themselves, although armour in sauropods overall is uncommon.
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The authors consider the animal to have had an intermediate phylogenetic position between Liaoceratops and Archaeoceratops within Neoceratopia. Examination of the frill of Yamaceratops has convinced the authors that the frill was not used for display, and that the fossils "[hint] at a more complex evolutionary history for ceratopsian frills." The genus name refers to Yama, a Tibetan Buddhist deity; the species name to the Eastern Gobi. The holotype IGM 100/1315 consists of a partial skull; other material has been found in 2002 and 2003 and has been ascribed to the genus.
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The majority of Jehol flora has been discovered in the lower Yixian Formation. This flora includes most groups of Mesozoic plants, including mosses, clubmosses, horsetails, ferns, seed ferns, Czekanowskiales, ginkgo trees, cycadeoids, Gnetales, conifers, and a small number of flowering plants. Fauna that were present in the Jehol Biota include ostracods, gastropods, bivalves, insects, fish, salamanders, mammals, lizards, choristoderes, pterosaurs, and dinosaurs (including birds). These dinosaur fossils are exceptionally well preserved, frequently preserving feather impressions and sometimes even pigmentation, such as in Microraptor (an aerial predator), Psittacosaurus (a small ceratopsian), and Sinosauropteryx (a compsognathid).
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Protoceratops (; from Greek '/ "first", '/ "horn" and '/ "face", meaning "first horned face") is a genus of sheep-sized (1.8 m long) herbivorous ceratopsian dinosaur, from the Upper Cretaceous Period (Campanian stage) of what is now Mongolia. It was a member of the Protoceratopsidae, a group of early horned dinosaurs. Unlike later ceratopsians, however, it was a much smaller creature that lacked well-developed horns and retained some basal traits not seen in later genera. Protoceratops had a large neck frill which was likely used as a display site to impress other members of the species.
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Reconstructed skeletons of an adult with juveniles P. sibiricus skull in front view Psittacosaurus is the type genus of the family Psittacosauridae, which was also named by Osborn in 1923. Psittacosaurids were basal to almost all known ceratopsians except Yinlong and perhaps the Chaoyangsauridae. While Psittacosauridae was an early branch of the ceratopsian family tree, Psittacosaurus itself was probably not directly ancestral to any other groups of ceratopsians. All other ceratopsians retained the fifth digit of the hand, a plesiomorphy or primitive trait, whereas all species of Psittacosaurus had only four digits on the hand.
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In addition, the antorbital fenestra, an opening in the skull between the eye socket and nostril, was lost during the evolution of Psittacosauridae, but is still found in most other ceratopsians and in fact most other archosaurs. It is considered highly unlikely that the fifth digit or antorbital fenestra would evolve a second time. In 2014, the describers of a new taxon of basal ceratopsian published a phylogenetic analysis encompassing Psittacosaurus. The below cladogram is from their analysis, placing the genus as one of the most primitive ceratopsians.
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Group of six juveniles that died together – specimen IVPP V14341 The find of a herd of six Psittacosaurus individuals killed and buried by a volcanic mudflow indicates the presence of at least two age groups from two distinct clutches gathered together. This find has been taken as evidence for group fidelity and gregariousness extending beyond the nest; the earliest such evidence for any ceratopsian. Even very young psittacosaur teeth appear worn, indicating they chewed their own food and may have been precocial. Another juvenile-only cluster shows that specimens of different ages grouped together.
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Individually these teeth were not suitable for grinding food, but when joined together with other teeth they would form a large surface area for the mechanical digestion of tough plant materials. This type of dental strategy is observed in ornithopod and ceratopsian dinosaurs as well as the duck-billed hadrosaurs, which had more than one hundred teeth in each dental battery. The teeth of carnivorous dinosaurs, called ziphodont, were typically blade-like or cone-shaped, curved, with serrated edges. This dentition was adapted for grasping and cutting through flesh.
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The generic name is derived from , brachys, "short", , keras, "horn" and , ops, "face", in reference to the short snout. The specific name refers to the provenance from Montana.C.W. Gilmore, 1914, "A new ceratopsian dinosaur from the Upper Cretaceous of Montana, with note on Hypacrosaurus", Smithsonian Miscellaneous Collections 63(3): 1-10 Norman Ross completing the Smithsonian mount All that was found were incomplete and jumbled remains of five juvenile individuals of about 1.5 m (5 feet) in length. It has been speculated that these juveniles may have been nest mates that stayed together after hatching.
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The generic name is a combination of Turan, an old Persian name for Turkestan, the general region of the finds, and ~ceratops, "horned face", a usual suffix in ceratopian names. The specific name means "retarding" in Latin, referring to the protracted research.L.A. Nessov, F. Kaznyshkina, & G.O. Cherepanov, 1989, "Ceratopsian dinosaurs and crocodiles of the middle Mesozoic of Asia", In: Bogdanova & Khozatsky (eds.) Theoretical and applied aspects of modern paleontology, pp 142-149 The holotype, CCMGE No. 251/12457, consists of a damaged left maxilla, the tooth- bearing upper jaw bone.
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In 1987 and 1989, horned dinosaur specialist Peter Dodson was invited to investigate the new ceratopsian finds. In 1990, the fossil material was seen by Dodson as strengthening the case for the validity of a separate Styracosaurus ovatus, to be distinguished from Styracosaurus albertensis. Meanwhile, Horner had come to a more complex view of the situation. He still thought that the fossil material had been part of a single population but concluded that this had developed over time as a chronospecies evolving into a series of subsequent taxa.
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In 1990, this name, as an invalid nomen nudum because it lacked a description, appeared in a photo caption in a book by Stephen Czerkas. Postorbital bones Horner was an expert on the Hadrosauridae, several sites of which had also been discovered in Landslide Butte, including the juveniles and eggs that were the focus of his research. He had less affinity for other kinds of dinosaurs. In 1987 and 1989, to resolve the Styracosaurus question, horned dinosaur specialist Peter Dodson was invited to investigate the new ceratopsian finds.
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Their function has been the subject of debate since the first horned dinosaurs were discovered. Common theories concerning the function of ceratopsian frills and horns include defense from predators, combat within the species, and visual display. A 2009 study of Triceratops and Centrosaurus skull lesions found that bone injuries on the skulls were more likely caused by intraspecific combat (horn-to-horn combat) rather than predatory attacks. The frills of Centrosaurus were too thin to be used for defense against predators, although the thicker, solid frills of Triceratops might have evolved to protect their necks.
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Studies of bone histology show that Kosmoceratops grew rapidly and had an elevated metabolism, similar to modern birds and mammals. The teeth of ceratopsids were adapted to processing fibrous plants; coprolites (fossilized dung) from the Kaiparowits Formation that contain wood may have been produced by ceratopsids. The functions of ceratopsian frills and horns have been debated, including display, combat, and species recognition. The Kaiparowits Formation dates to the late Campanian age and was deposited on Laramidia, an island continent, when North America was divided at the center by the Western Interior Seaway.
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M. A. Getty, M. A. Loewen, E. M. Roberts, A. L. Titus, and S. D. Sampson. 2010. Taphonomy of horned dinosaurs (Ornithischia: Ceratopsidae) from the late Campanian Kaiparowits Formation, Grand Staircase-Escalante National Monument, Utah. In M. J. Ryan, B. J. Chinnery-Allgeier, D. A. Eberth (eds.), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press, Bloomington 478-494 It was first named and described in a thesis by its discoverer Eric Karl Lund in 2010 as Nasutuceratops titusi, remaining at first an invalid nomen ex dissertatione.
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Thomas M. Lehman has observed that Corythosaurus and Centrosaurus haven't been discovered outside of southern Alberta even though they are the most abundant Judithian dinosaurs in the region. Large herbivores like the ceratopsians and hadrosaurs living in North America during the Late Cretaceous had "remarkably small geographic ranges" despite their large body size and high mobility. This restricted distribution strongly contrasts with modern mammalian faunas whose large herbivores' ranges "typical[ly] ... span much of a continent." Another example is Pentaceratops, the only known Judithian ceratopsian from New Mexico.
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Prenoceratops, (meaning 'bent or prone-horned face' and derived from Greek prene-/πρηνη- meaning 'bent forwards' or 'prone', cerat-/κερατ- meaning 'horn' and -ops/ωψ meaning 'face') is a genus of ceratopsian dinosaur from the Late Cretaceous Period. Its fossils have been found in the upper Two Medicine Formation in the present-day U.S. state of Montana, in Campanian age rock layers that have been dated to 74.3 million years ago.Ryan, M. J., Evans, D. C., Currie, P. J., Brown, C. M., & Brinkman, D. (2012). New leptoceratopsids from the Upper Cretaceous of Alberta, Canada.
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Longosuchus meadei (an aetosaur), Gavialis gangeticus, (a crocodilian), Saurosuchus galilei (a loricatan), Pedeticosaurus leviseuri (a sphenosuchian), Chenanisuchus lateroculi (a dyrosaurid), and Dakosaurus maximus (a thalattosuchian). Tupuxuara leonardi (a pterosaur), Alamosaurus sanjuanensis, (a sauropod), Tsintaosaurus spinorhinus (an ornithopod), Daspletosaurus torosus (a tyrannosaurid), Pentaceratops sternbergii (a ceratopsian), and Grus grus (a neornithian). Since the 1970s, scientists have classified archosaurs mainly on the basis of their ankles.Archosauromorpha: Archosauria - Palaeos The earliest archosaurs had "primitive mesotarsal" ankles: the astragalus and calcaneum were fixed to the tibia and fibula by sutures and the joint bent about the contact between these bones and the foot.
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The god Set was associated with the hippopotamus, therefore fossilized bones of hippo-like species were kept in that deity's temples. Five-rayed fossil sea urchin shells were associated with the deity Sopdu, the Morning Star, equivalent of Venus in Roman mythology. Ceratopsian skulls are common in the Dzungarian Gate mountain pass in Asia, an area once famous for gold mines, as well as its endlessly cold winds. This has been attributed to legends of both gryphons and the land of Hyperborea Fossils appear to have directly contributed to the mythology of many civilizations, including the ancient Greeks.
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Mesozoic Meanderings 2 196 pp However, Dodson objected against this change, arguing the genitive singular might also refer to a single family name. In 1990 Thomas Lehman renamed A. lammersi into Monoclonius lammersi;Lehman, T.M., 1990, "The ceratopsian subfamily Chasmosaurinae: sexual dimorphism and systematics". In: K. Carpenter and P. J. Currie (eds.), Dinosaur Systematics: Perspectives and Approaches, Cambridge University Press, Cambridge pp 211-229 This alternative name has found no acceptance. The holotype, ANSP 15800, consists of a partial skeleton containing the lower skull, a left lower jaw, vertebrae, a complete shoulder girdle and most elements of forelimbs and hindlimbs.
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Early members of the ceratopsian group, such as Psittacosaurus, were small bipedal animals. Later members, including ceratopsids like Centrosaurus and Triceratops, became very large quadrupeds and developed elaborate facial horns and frills extending over the neck. While these frills might have served to protect the vulnerable neck from predators, they may also have been used for display, thermoregulation, the attachment of large neck and chewing muscles or some combination of the above. Ceratopsians ranged in size from 1 meter (3 ft) and 23 kilograms (50 lb) to over 9 meters (30 ft) and 9,100 kg (20,100 lb).
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Hunt-Foster's current research includes Early Cretaceous ornithomimosaurs from North America, the Upper Cretaceous Williams Fork Formation paleofauna of western Colorado, the ichnofauna of the lower Jurassic to lower Cretaceous rocks of southeastern Utah. ReBecca has worked as a paleontologist in western Colorado and eastern Utah since 2007. Prior to moving to the area, ReBecca was a research assistant at Augustana College where she worked on latest Cretaceous ceratopsian dinosaurs from southern Laramidia and preparing Cryolophosaurus, the first known dinosaur from Antarctica. She has also worked on Precambrian stromatolites and the geology of Glacier National Park.
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Restoration of the earliest known dromaeosaurid, 2015 Several of Csotonyi's drawings can be seen on signs along the Alberta's Fossil Trail, commissioned by the Royal Tyrrell Museum of Palaeontology (Drumheller, Canada). In 2007, he was commissioned by this museum to illustrate their new ceratopsian permanent exhibit in Dinosaur Hall. He also produced the main illustration for the Tyrrell Museum’s website. In 2008 he completed a mural for the exhibit Dinosaur Mummy CSI: Cretaceous Science Investigation of the Houston Museum of Natural Science, featuring a mummified Brachylophosaurus nicknamed "Leonardo" (the Guinness Book of World Record's best preserved dinosaur).
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Koreaceratops is a genus of basal ceratopsian dinosaur discovered in Albian- age Lower Cretaceous rocks of South Korea. It is based on KIGAM VP 200801, an articulated series of 36 caudal vertebrae associated with partial hind limbs and ischia. This specimen was found in a sandstone block that had been incorporated into the Tando dam at Hwaseong City; the way the specimen is cut off suggests that more of it was present before quarrying. The dam was built in 1994, and the bones were first brought to the attention of paleontologists in 2008, after a public official noticed them.
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Size comparison Sinoceratops was a larger ceratopsian ornithischian, with an estimated length of about , weight of , and height of about . Thomas R. Holtz Jr. estimated its length at and weight at , the weight of a rhinoceros. It has a short, hooked horn on its nose (called a nasal horn), no horns above its eyes (brow horns), and a short neck frill with a series of forward-curving hornlets that gave the frill a crown-like appearance. Inside this row of hornlets there is a series of low knobs on the top of the frill, which are not seen in any other horned dinosaur.
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By the 1980s, the affinities of the pachycephalosaurs within Ornithischia were unresolved. The main competing views were that the group was closest to either ornithopods or ceratopsians, the latter view due to similarities between the skeleton of Stegoceras and the "primitive" ceratopsian Protoceratops. In 1986, American palaeontologist Paul Sereno supported the relationship between pachycephalosaurs and ceratopsians, and united them in the group Marginocephalia, based on similar cranial features, such as the "shelf"-structure above the occiput. He conceded that the evidence for this grouping was not overwhelming, but the validity of the group was supported by Sues and Galton in 1987.
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Restoration of Einiosaurus and Maiasaura in environment Einiosaurus fossils are found in the upper part of the Two Medicine Formation of Montana, dating to the mid-late Campanian stage of the late Cretaceous Period, about 74.5 million years ago.Andrew T. McDonald & John R. Horner, (2010). "New Material of "Styracosaurus" ovatus from the Two Medicine Formation of Montana". Pages 156–168 in: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, Bloomington and Indianapolis, IN.Fiorillo, A.R. and Tykoski, R.S.T. (in press).
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The findings also include the remains of a 20-meter (66 ft) hadrosaurid, a record size for the duck-billed dinosaur. A fossilized skull of a large ceratopsian was also found along with bones which belong to club-tailed ankylosaurs. According to Professor Zhao Xijin, a palaeontologist in charge of the excavations from the Institute of Vertebrate Paleontology and Paleoanthropology, "This group of fossilised dinosaurs is currently the largest ever discovered in the world... in terms of area." Such a high concentration of fossil bones in such a small area is significant for the theories of extinction of dinosaurs.
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Restoration Anchiceratops is rare compared to other ceratopsians in the area, and usually found near marine sediments, in both the Horseshoe Canyon and Dinosaur Park Formations. This indicates that Anchiceratops may have lived in estuaries where other ceratopsids did not live. Flowering plants were increasingly common but still rare compared to the conifers, cycads and ferns which probably made up the majority of ceratopsian diets. In 1914 Brown suggested that the distinctive frill and horn form of Anchiceratops were caused by sexual selection and intra-species recognition, as he could not explain the differences between the taxa by a difference in defence function.
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Arrhinoceratops (meaning "no nose-horn face", derived from the Ancient Greek "a-/α-" "no", rhis/ῥίς "nose" "keras/κέρας" "horn", "-ops/ὤψ" "face") is a genus of herbivorous ceratopsian dinosaur. The name was coined as its original describer concluded it was special because the nose-horn was not a separate bone, however further analysis revealed this was based on a misunderstanding. It lived during the latest Campanian/earliest Maastrichtian stage of the Late Cretaceous, predating its famous relative Triceratops by a few million years, although it was contemporary with Anchiceratops. Its remains have been found in Canada.
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The question mark indicates that Gilmore himself had doubts about the identification.C.W. Gilmore, 1946, "Reptilian fauna of the North Horn Formation of central Utah", United States Department of the Interior Geological Survey Professional Paper 210-C: 29-53 In 1976, Douglas A. Lawson transferred the species to Torosaurus, as a Torosaurus utahensis.D.A. Lawson, 1976, "Tyrannosaurus and Torosaurus, Maestrichtian dinosaurs from Trans-Pecos, Texas", Journal of Paleontology 50(1): 158-164Hunt, R.K. and Lehman, T.M. (2008). "Attributes of the ceratopsian dinosaur Torosaurus, and new material from the Javelina Formation (Maastrichtian) of Texas". Journal of Paleontology 82(6): 1127-1138.
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The holotype specimen IGM 100/29 (Mongolian Academy of Sciences, Ulan Bator, Mongolia) consists of an almost complete and articulated but compressed skeleton, lacking only portions of the pectoral girdle, pelvic girdle, and hindlimbs. It was recovered in the Dundgovi Aimag (Eastern Gobi Province), from an exposure of the Shinekhudag Formation now part of the Khuren Dukh Formation which dates to the Mid-Late AlbianBarsbold, R. and Perle, A. (1984). [On first new find of a primitive orithomimosaur from the Cretaceous of the MPR]. Paleontologicheskii zhurnal, 2: 121-123 Other dinosaurs collected from the Shinekhudug Formation in Dundgovi include the ceratopsian Psittacosaurus mongoliensis.
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The latter two genera, which lived later than Camptosaurus, had somewhat higher EQs than the Jurassic taxon, which, being at the lower end, was more comparable to the ceratopsian genus Protoceratops. Reasonings suggested for their comparably high intelligence were the need for acute senses in the lack of defensive weapons, and more complex intraspecific behaviours as indicated by their acoustic and visual display structures. In a first for any terrestrial fossil vertebrate, Brasier et al. (2017) reported mineralized soft tissues from the brain of an iguanodontian dinosaur, from the Valanginian age (around 133 million years ago) Upper Tunbridge Wells Formation at Bexhill, Sussex.
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Skull of oviraptorid specimen GIN 100/42 The diet of oviraptorids is not fully understood. Though some appear to have been at least partially carnivorous, they were probably primarily herbivorous. Originally, oviraptorids were thought to be specialized egg raiders, based on a Mongolian find showing Oviraptor on top of a nest erroneously attributed to the ceratopsian dinosaur Protoceratops. However, discoveries in the 1990s, including Citipati specimens clearly brooding (rather than preying on) the same types of nests, and a Citipati embryo inside the same type of egg preserved in these nests, showed that the "specialized egg thief" idea was incorrect.
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Life restoration of Parksosaurus warreni Parksosaurus is known from the base of Unit 4 of the Horseshoe Canyon Formation, which dates to about 69.5 million years ago. Other dinosaur species from this same unit include the theropods Albertosaurus sarcophagus and Albertavenator curriei as well as the spike- crested hadrosaurid Saurolophus osborni, hollow-crested hadrosaurid Hypacrosaurus altispinus, and ankylosaurid Anodontosaurus lambei. Teeth of an unidentified ceratopsian species are known from the same stratigraphic level. The dinosaurs from this formation are sometimes known as Edmontonian, after a land mammal age, and are distinct from those in the formations above and below.
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Characteristic dinosaur taxa include the ceratopsian Torosaurus utahensis, the titanosaurid sauropod Alamosaurus sanjuanensis, and the theropod Tyrannosaurus;Sampson, S.D., Loewen, M.A.(2005). Tyrannosaurus from the Upper Cretaceous (Maastrichtian) North Horn Formation of Utah: biogeographic and paleoecologic implications. Journal of Vertebrate Paleontology 25:2, 469-472 however, the most frequently occurring taxon in the Cretaceous strata of the North Horn Formation is the Polyglyphanodont squamate Polyglyphanodon. Fauna recorded from Paleocene strata within the formation appear to be far more diverse and over 70 different taxa have been identified, including frogs, numerous multituberculate, protoeutherians, periptychids, arctocyonids and phenacodontid mammals, crocodyliforms, choristoderes, trace fossils, and palynomorphs.
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Restoration of two running specimens Avaceratops was by Dodson in 1986 assigned to the Ceratopsidae within the Ceratopsia (both names being derived from Ancient Greek for 'horned face'), a group of herbivorous dinosaurs with parrot-like beaks which thrived in what are now North America and Asia, during the Cretaceous Period. Apart from being a ceratopsian, little is certain about Avaceratops's taxonomic position. Because most of the skeleton is only known from a juvenile, and juveniles tend to express ancestral traits more strongly, a cladistic analysis would likely indicate a too basal, low, position in the evolutionary tree. For this reason, Avaceratops has often been excluded from such analyses.
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Nigersaurus taqueti teeth Although all authorities agree that the rebbachisaurids are members of the superfamily Diplodocoidea, they lack the bifid (divided) cervical neural spines that characterise the diplodocids and dicraeosaurids, and for this reason are considered more primitive than the latter two groups. It is not yet known whether they share the distinctive whip-tail of the latter two taxa. Rebbachisaurids are distinguished from other sauropods by their distinctive teeth, which have low angle, internal wear facets and asymmetrical enamel. Unique among sauropods, at least some rebbachisaurids (such as Nigersaurus) are characterised by the presence of tooth batteries, similar to those of hadrosaur and ceratopsian dinosaurs.
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For much of its history, the museum was known as the "Humboldt Museum",See page 19: "MB: Berlin Museum für Naturkunde (formerly Humboldt Museum für Naturkunde)" in Kenneth Carpenter, Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs, Indiana University Press, 384 pages, 2006, but in 2009 it left the university to join the Leibniz Association. The current official name is Museum für Naturkunde – Leibniz- Institut für Evolutions- und Biodiversitätsforschung and the "Humboldt" name is no longer related to this museum. Furthermore: there is another Humboldt- Museum in Berlin in Tegel Palace dealing with brothers Wilhelm and Alexander von Humboldt. The Berlin U-Bahn station Naturkundemuseum is named after the museum.
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According to Scott D. Sampson, if ceratopsids were to have sexual dimorphism modern ecological analogues suggest it would be in their mating signals like horns and frills. No convincing evidence for sexual dimorphism in body size or mating signals is known in ceratopsids, although was present in the more primitive ceratopsian Protoceratops andrewsi whose sexes were distinguishable based on frill and nasal prominence size. This is consistent with other known tetrapod groups where midsized animals tended to exhibit markedly more sexual dimorphism than larger ones. However, if there were sexually dimorphic traits they may have been soft tissue variations like colorations or dewlaps that would not have been preserved as fossils.
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The mega-bonebed is located 25 kilometers west of the town of Hilda, Alberta in a "steep-walled" valley cut into the landscape by glaciers during the Pleistocene epoch. Northward through this valley's interior runs the South Saskatchewan River. The individual bonebeds in the complex are recognizable as dense concentrations of ceratopsid bones. Research on the bonebeds of Dinosaur Provincial Park has discovered that ceratopsian bonebeds preserved in mudstone deposits tended to be circular to ovular in shape when viewed from above, so the similar Hilda bonebeds probably were as well. H97-04 is the largest of the fourteen bonebeds, at 150 m in width.
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In 1922 the British had been awarded German East Africa as part of the settlement of World War I. Within the Tanganyika Territory the Germans had discovered a site rich in dinosaur fossils, Tendaguru. Louis was told by C. W. Hobley, a friend of the family, that the British Museum of Natural History was going to send a fossil-hunting expedition led by William E. Cutler to the site. Louis applied and was hired to locate the site and manage the administrative details.New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium editors Michael J. Ryan, Brenda J. Chinnery-Allgeier, David A. Eberth.
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The theme of Janet Jackson's song "China Love" was related to the film by MTV News, in which Jackson sings of the daughter of an emperor in love with a warrior, unable to sustain relations when forced to marry into royalty. The names of the pterosaur genus Kryptodrakon and the ceratopsian genus Yinlong (both meaning hidden dragon in Greek and Mandarin respectively) allude to the film. The character of Lo, or "Dark Cloud" the desert bandit, influenced the development of the protagonist of the Prince of Persia series of video games."Prince of Persia: Anatomy of a Prince", PlayStation: The Official Magazine 13 (December 2008): 50.
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Ischioceratops is an extinct genus of small ceratopsian dinosaur that lived approximately 69 million years ago during the latter part of the Cretaceous Period in what is now China. Ischioceratops was a small sized, moderately- built, ground-dwelling, quadrupedal herbivore, whose total body length has been estimated to be about 2 meters. The ceratopsians were a group of dinosaurs with parrot-like beaks which fed on vegetation and thrived in North America and Asia during the Cretaceous Period, which ended approximately 66 million years ago, at which point they all became extinct. Its name means "ischium horned face", referring to the peculiar shape of the ischiatic bones.
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A, Triceratops prorsus holotype YPM 1822 and B, Torosaurus latus ANSP 15192 John Scannella, in a paper presented in Bristol, UK at the conference of the Society of Vertebrate Paleontology (September 25, 2009) reclassified Torosaurus as especially mature Triceratops individuals, perhaps representing a single sex. Jack Horner, Scannella's mentor at Bozeman Campus, Montana State University, noted that ceratopsian skulls consist of metaplastic bone. A characteristic of metaplastic bone is that it lengthens and shortens over time, extending and resorbing to form new shapes. Significant variety is seen even in those skulls already identified as Triceratops, Horner said, "where the horn orientation is backwards in juveniles and forward in adults".
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Pie chart of the time averaged census for large-bodied dinosaurs from the entire Hell Creek Formation in the study area Triceratops lived during the Late Cretaceous of North America, its fossils coming from the Evanston Formation, Scollard Formation, Laramie Formation, Lance Formation, Denver Formation, and Hell Creek Formation. These fossil formations date back to the time of the Cretaceous–Paleogene extinction event, which has been dated to 66 ± 0.07 million years ago. Many animals and plants have been found in these formations, but mostly from the Lance Formation and Hell Creek Formation. Triceratops was one of the last ceratopsian genera to appear before the end of the Mesozoic.
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Styracosaurus ( ; meaning "spiked lizard" from the Ancient Greek styrax/στύραξ "spike at the butt-end of a spear-shaft" and sauros/σαῦρος "lizard") is a genus of herbivorous ceratopsian dinosaur from the Cretaceous Period (Campanian stage), about 75.5 to 75 million years ago. It had four to six long parietal spikes extending from its neck frill, a smaller jugal horn on each of its cheeks, and a single horn protruding from its nose, which may have been up to long and wide. The function or functions of the horns and frills have been debated for many years. Styracosaurus was a relatively large dinosaur, reaching lengths of and weighing nearly 3 tonnes.
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The upper assemblage also has a tyrannosaurid, a ceratopsian, and a pachycephalosaur. Although not a dinosaur, the primitive mammal Gobiconodon is known from both Mongolia and the Mussentuchit Member. Evidence for a middle dinosaur assemblage between the older and younger ones is controversial because the evidence mostly depends on a single specimen of the ornithopod Tenontosaurus from high in the Ruby Ranch Member and the sauropod Astrodon from low in the Ruby Ranch. Regardless, the upper and lower dinosaur assemblages in the Cedar Mountain Formation document the separation of North America and Europe, the westward drift of North America, and its connection with Asia 10 to 15 million years later.
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Coronosaurus is a genus of centrosaurine ceratopsian dinosaurs which lived in the Late Cretaceous, in the middle Campanian stage. Its remains, two bone beds, were discovered by Phillip J. Currie in the Oldman Formation of Alberta, Canada, and its type and only species, Coronosaurus brinkmani, was first described in 2005, as a new species within the genus Centrosaurus. Later studies questioned the presence of a direct relationship, and in 2012 it was named as a separate genus. Coronosaurus means "crowned lizard", coming from "corona", Latin for crown, and "sauros", Greek for lizard; this name refers to the unique, crown-like shape of the horns on the top of its frill.
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The Kyzylkum is between the Syr-Darya and Amu-Darya Rivers The Kyzylkum Desert has exposed rock formations that have yielded a number of fossils. Of particular interest is the Bissekty Formation of Uzbekistan, from the early Late Cretaceous, which has produced several species of early birds: Incolornis martini, Explorornis walkeri, Kizylkumavis cretacea, Kuszholia mengi, Lenesornis kaskarovi, Sazavis prisca, Zhyraornis kaskarovi and Z. logunovi are recognized as valid species. Tyrannosaurid, therizinosaurid, ornithomimosaur, oviraptorosaurian, troodontid, ankylosaur, hadrosaur, and ceratopsian dinosaurs are also known from this rock unit. Other fossils from the Cretaceous rocks of the Kyzylkum include tree trunks, pelecypods, beetles, sharks, rays, bony fish, frogs, salamanders, turtles, crocodylomorphs, pterosaurs, and a varied fauna of small early mammals.
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From the Cenomanian to the end of the Campanian ages of the Late Cretaceous, Appalachia was separated from the rest of North America. As the Western Interior Seaway retreated in the Maastrichtian, Laramidia and Appalachia eventually connected. Because of this, its fauna was isolated, and developed very differently from the tyrannosaur, ceratopsian, hadrosaurid, pachycephalosaur and ankylosaurid dominated fauna of the western part of North America, known as "Laramidia". Due to high sea levels, subsequent erosion, and the lack of orogenic input of sediment into the Western Interior Seaway unlike the east coast of Laramidia, no terrestrially formed deposits have survived, with most dinosaur remains originating from seaborne carcasses that were transported into marine environments.
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However, Cirrus flies Will to ancient ruins in the jungle of which the Tyrannosaurus are strangely protective. Arthur, Oriana, Bix, and Lee continue to explore the caverns underneath Dinotopia where they come across instantly germinating fern spores, uncut sunstones that appear to store ancestral memory, and mechanical limbs that twitch when the sunstone is brought near. Eventually, they reach an enormous man-made chamber filled with abandoned walking vehicles modelled after prehistoric animals, left behind by the ancient civilization of Poseidos, which they nickname "Strutters". Arthur, Oriana, and Bix commandeer a ceratopsian strutter while Crabb takes a strutter modeled after a sea scorpion and they both climb out of the World Beneath, ending up in the Rainy Basin.
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Skeletons of P. andrewsi and Velociraptor mongoliensis in combat Photographer James Blaine Shackelford discovered the first specimen of Protoceratops in the Gobi desert, (Gansu, Inner Mongolia), as part of a 1922 American expedition looking for human ancestors. No early human fossils were found, but the expedition, led by Roy Chapman Andrews, collected many specimens of the genus Protoceratops, along with fossil skeletons of theropods Velociraptor, Oviraptor, and ceratopsian Psittacosaurus. Walter Granger and W. K. Gregory formally described the type species, P. andrewsi in 1923, the specific name in honor of Andrews. The fossils hail from the Djadochta Formation and date from the Campanian stage of the Upper Cretaceous (dating to between 75 and 71 million years ago).
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In 1890 Marsh renamed Hadrosaurus paucidens into Ceratops paucidens; but the original assessment of Hatcher that this represented hadrosaurid material is probably correct. In 1905 Hatcher renamed three Monoclonius species into Ceratops species: Monoclonius recurvicornis Cope 1889 became Ceratops recurvicornis; Monoclonius belli Lambe 1902 was made Ceratops belli and Monoclonius canadensis Lambe 1902 was renamed Ceratops canadensis. C. canadensis later was made the separate genus Eoceratops, and C. belli was made the separate genus Chasmosaurus; in 1925 William King Gregory concluded that Ceratops and Chasmosaurus were identical, but this was rejected by most researchers. In 2005, remarkably well preserved cranial and postcranial elements of a Judithian ceratopsian were discovered in Fergus County, Montana.
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In the Cretaceous Period, sauropods in North America were no longer the dominant group of herbivorous dinosaurs, with the ornithopod and ceratopsian dinosaurs, such as Edmontosaurus and Triceratops, becoming the most abundant (this being most evident by the Late Cretaceous epoch). However, on other landmasses such as South America and Africa (which were island continents much like modern Australia) sauropods, in particular the titanosaurs, continued to be the dominant herbivores. Saltasaurus was one such titanosaur sauropod, and lived around 70 million years ago. When it was first discovered, in 1975, it forced palaeontologists to reconsider some assumptions about sauropods as Saltasaurus possessed crocodile-like armour (osteoderms) 10 to 12 centimetres (4 to 5 in) in diameter.
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Kosmoceratops () is a genus of ceratopsid dinosaur that lived in North America about 76.4–75.5 million years ago during the Late Cretaceous period. Specimens were discovered in Utah in the Kaiparowits Formation of the Grand Staircase- Escalante National Monument in 2006 and 2007, including an adult skull and postcranial skeleton and partial subadults. In 2010, the adult was made the holotype of the new genus and species Kosmoceratops richardsoni; the generic name means "ornate horned face", and the specific name honors Scott Richardson, who found the specimens. The find was part of a spate of ceratopsian discoveries in the early 21st century, and Kosmoceratops was considered significant due to its elaborate skull ornamentation.
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Its clade would differ from the northern centrosaurines in the retention of long brow horns and a short nose horn, combined with developing, convergent with the Chasmosaurinae, low epiparietals. In 2016, this clade was named Nasutoceratopsini; it contains Nasutoceratops as well as ANSP 15800 (the holotype of Avaceratops), MOR 692 (previously treated as an adult specimen of Avaceratops), the newly-described CMN 8804 from the Oldman Formation, and another undescribed ceratopsian found in Malta, Montana. The cladogram presented below follows a phylogenetic analysis of the Centrosaurinae by Chiba et al. (2017), which included a systematic re-evaluation of Medusaceratops lokii: Ceratopsid skull casts positioned in a phylogenetic tree; Nasutoceratops is located middle left (06).
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Another example is Pentaceratops, the only known Judithian ceratopsian from New Mexico. In modern North America if one was to sample hypothetical future sites in southwestern Texas, northern New Mexico and southern Alberta, 34 of the 41 large mammal species in the continent could be represented, with the remainder's geographic ranges not overlapping with the sites. Roughly 20 species would be located at each site, but contrasting with the provinciality of dinosaurs, 11-16 species out of twenty would be shared between all three sites. Only the rarer species among modern mammal communities would be able to distinguish different latitudinal zones, and some of these taxa are likely too rare to fossilize.
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The Kirtlandian faunal age of the Cretaceous period follows the Judithian and is succeeded by the Edmontonian. It is Campanian in age and is characterized by the ceratopsian Pentaceratops sternbergii, which lived throughout the Kirtlandian. The geological formations found to date or persist from the Kirtlandian are the Bearpaw, the upper Kaiparowits Formation, the Kirtland, Fruitland, Williams Fork, Fort Crittenden, Ringbone, Corral de Enmedio, Packard, and El Gallo formations, and possibly the lower part of the Cerro del Pueblo Formation and upper region of the Aguja Formation. These formations are exposed in Alberta and Montana, Utah, New Mexico, New Mexico, Colorado, Arizona, New Mexico, Sonora, Baja California, Baja California, and possibly Coahuila, and Texas, respectively.
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No convincing evidence for sexual dimorphism in body size or mating signals is known in ceratopsids, although there is evidence that the more primitive ceratopsian Protoceratops andrewsi possessed sexes that were distinguishable based on frill and nasal prominence size. This is consistent with other known tetrapod groups where midsized animals tend to exhibit markedly more sexual dimorphism than larger ones. However, it has been proposed that these differences can be better explained by intraspecific and ontogenic variation rather than sexual dimorphism. In addition, many sexually dimorphic traits that may have existed in ceratopsians include soft tissue variations such as coloration or dewlaps, which would be unlikely to have been preserved in the fossil record.
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A small rostral bone on the end of the upper jaw clearly identifies Yinlong as a ceratopsian, although the skull displays several features, especially the ornamentation of the squamosal bone of the skull roof, which were previously thought to be unique to pachycephalosaurians. The presence of these features in Yinlong indicates these as actual synapomorphies (unique features) of the larger group Marginocephalia, which contains both the pachycephalosaurs and the ceratopsians, although these features have been lost in all known ceratopsians more derived than Yinlong. The addition of these characters further strengthens the support for Marginocephalia. Yinlong also preserves skull features reminiscent of the family Heterodontosauridae, providing support for the hypothesis that heterodontosaurids are closely related to marginocephaliansZhao X., Cheng Z., & Xu X. 1999.
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The main focus of the article by Sampson and colleagues was how these three ceratopsian genera provided new evidence for reconstructing the paleobiogeography of their time and place. In a 2010 press release announcing the study, Sampson described Kosmoceratops as "one of the most amazing animals known, with a huge skull decorated with an assortment of bony bells and whistles", and considered Grand Staircase-Escalante "one of the country's last great, largely unexplored dinosaur boneyards". In 2017, the US government announced plans to shrink the Grand Staircase-Escalante (to little over half its size) and Bears Ears monuments to enable coal mining and other energy development on the land, which was the largest reduction of US national monuments in history.
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Unlike other bigger-budgeted movies that have used state-of-the-art effects (i.e., stop motion, puppets, etc.) for the dinosaurs, this movie uses the cheaper "man in a suit" method, much like the Godzilla movies of the 1960s and 1970s (the sound department even borrowed Godzilla's trademark roar and occasionally mixed it into the T. rex's roar). The "ceratopsian" (Uintatherium), as well as the Triceratops, were done through the "two guys in a horse-suit" technique. The scale (size) of the Tyrannosaurus also changes literally from scene to scene, in some cases it appears to be over 40–50 feet tall (when it attacks the borer) and can carry it in its mouth, when the Polar Borer is easily well over 10 feet in diameter.
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Skeleton of a juvenile in Maryland In what is now Maryland, Astrodon shared its paleoenvironment with dinosaurs such as coelurosaurians, the ankylosaurian Priconodon crassus, the nodosaurid Propanoplosaurus marylandicus, a possible basal ceratopsian, and potentially the ornithopod Tenontosaurus. The fossil evidence points to the presence of the poorly known theropods Dryptosaurus medius, Capitalsaurus potens and Coelurus gracilis, and the well known large theropod Acrocanthosaurus atokensis, which likely were the apex predators in this region. Other vertebrates are not as well known from the formation, but include freshwater sharks, lungfish, at least three genera of turtles including Glyptops caelatus and the crocodilian Goniopholis affinis. Evidence has shown that the multituberculate early mammal Argillomys marylandensis was also present.R. L. Cifelli, C. L. Gordon, and T. R. Lipka. 2013.
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This specimen bears a uniquely long, slender and downcurved upper jaw, suggesting that it was an animal with a specialized feeding strategy, yet another example of speciation on an island environment. Recently, a ceratopsian teeth were unearthed in Mississippi's Owl Creek Formation, which have been dated to be 67 million years old. The owner of this one particular tooth was probably a chasmosaurine since by the end of the Cretaceous, the centrosaurines had completely vanished from North America, though they were thriving in Asia as in the case of Sinoceratops. While leptoceratopsid remains, the few that have been discovered in recent years, have been unearthed in the southern part of Appalachia, they appear to be completely absent from the northern part of Appalachia, states like New Jersey, Delaware, and Maryland.
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The type species is Ojoceratops fowleri. It is very similar to its close relative Triceratops, though it is from an earlier time period and has a more squared-off frill.Robert M. Sullivan and Spencer G. Lucas, 2010, "A New Chasmosaurine (Ceratopsidae, Dinosauria) from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico", In: Ryan, M.J., Chinnery-Allgeier, B.J., and Eberth, D.A. (eds.) New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Bloomington, Indiana University Press, 656 pp. Nick Longrich, in 2011, noted that the squared-off frill is also found in some true Triceratops specimens and that Ojoceratops is probably a junior synonym of Triceratops, while Holtz (2010) noted that it is probably ancestral to Triceratops and possibly synonymous with the contemporary Eotriceratops.
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"New Material of "Styracosaurus" ovatus from the Two Medicine Formation of Montana". Pages 156–168 in: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, Bloomington and Indianapolis, IN. This genus was named by Andrew T. McDonald and John R. Horner in 2010, and the type species is Rubeosaurus ovatus. Formerly this species was assigned to Styracosaurus.. It is notable for its large broad–based nasal horn and the ornamentation of its bony frill: there were one or two pairs of straight spikes on the edge, with the two spikes closest to the midline pointing so that they converged. Immature specimens referred to a separate genus, called Brachyceratops, may be juvenile Rubeosaurus.
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Left squamosal bone It contains a single species, M. cronusi, first described and named in 2016 by Eric K. Lund, Patrick M. O’Connor, Mark A. Loewen and Zubair A. Jinnah. The generic name is derived from Greek machairis, meaning "bent sword", in reference to its unique frill ornamentation showing two forward curving horns on the frill's uppermost part, and Latinized Greek ceratops, meaning "horned- face", which is a common suffix for ceratopsian genera names. The specific name cronusi refers to Cronus, a Greek god who deposed his father Uranus by castrating him with a sickle or scythe based on the mythology, and as such is shown carrying a curved bladed weapon. Machairoceratops is known solely from the holotype UMNH VP 20550, found in 2006, which is housed at the Natural History Museum of Utah.
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They proposed instead the new genus name Nemegtomaia ("maia" means "good mother" in Greek, and the full name means "good mother of the Nemegt"), making reference to the then-recent discovery that oviraptorids brooded eggs rather than stealing them, though no trace of a nest or eggs had yet been found associated with Nemegtomaia itself. The first known member of the oviraptorid family was found with a nest of eggs originally thought to have belonged to the ceratopsian genus Protoceratops, and was therefore named Oviraptor in 1924; this name means "egg-seizer". In the 1990s more oviraptorid specimens were discovered associated with nests and eggs, wherein oviraptorid embryos were found, thereby proving that the eggs belonged to the oviraptorids themselves. Ingenia was similarly renamed as Ajancingenia in 2013, since the former genus name was preoccupied by a roundworm (Nematoda).
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Velafrons (meaning "sailed forehead") is a genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Mexico. It is known from a mostly complete skull and partial skeleton of a juvenile individual, with a bony crest on the forehead. Its fossils were found in the late Campanian-age Cerro del Pueblo Formation (about 72 million years oldLoewen, M.A., Sampson, S.D., Lund, E.K., Farke, A.A., Aguillón-Martínez, M.C., de Leon, C.A., Rodríguez-de la Rosa, R.A., Getty, M.A., Eberth, D.A., 2010, "Horned Dinosaurs (Ornithischia: Ceratopsidae) from the Upper Cretaceous (Campanian) Cerro del Pueblo Formation, Coahuila, Mexico", In: Michael J. Ryan, Brenda J. Chinnery- Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, 656 pp.), near Rincon Colorado, Coahuila, Mexico. The type specimen is CPC-59, and the type species is V. coahuilensis.
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Ceratopsid skull casts positioned in a phylogenetic tree; Kosmoceratops is located middle right (10). The possible functions of ceratopsian horns and frills have been debated, including fighting off predators, species recognition, and temperature control, though the dominant hypothesis involves enhancing reproductive success. In a 2010 press release presenting Kosmoceratops, Utahceratops, and Vagaceratops, Sampson stated that most of these "bizarre features" would have been insufficient weapons against predators, but would have been used to intimidate or fight rivals of the same sex and attract individuals of the opposite sex. In 2011, paleontologists Kevin Padian and John R. Horner proposed that "bizarre structures" in dinosaurs (including horns, frills, domes, and crests) were primarily used for species recognition (to differentiate between sympatric species; related species that lived in the same area at the same time), and they dismissed other explanations as unsupported by evidence.
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Known elements from N. mckinleyi in blue, N. graffami in red and both species in purple The first fossil evidence later attributed to Nothronychus was discovered by a team of paleontologists working in the Zuni Basin of New Mexico at the Haystack Butte site, Moreno Hill Formation. A therizinosaur ischium (a hip bone) had originally been mistaken for a squamosal, a part of the skull crest of the newly discovered ceratopsian Zuniceratops. However, closer examination revealed the true identity of the bone, and soon more parts of the skeleton were found. The New Mexico team, led by paleontologists Jim Kirkland and Doug Wolfe, published their find in the Journal of Vertebrate Paleontology on 22 August 2001, making it the type specimen of the new species Nothronychus mckinleyi. The Arizona Republic newspaper, however, was first to announce the name on 19 June 2001, in a column by R.E. Molnar.
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Besides Siamosaurus, the dinosaur fauna of the Khok Kruat Formation included the carcharodontosaurid Siamraptor suwati; iguanodontians like Sirindhorna khoratensis, Ratchasimasaurus suranaerae, and Siamodon nimngami; a titanosauriform sauropod similar to Phuwiangosaurus; an indeterminate ceratopsian; and various indeterminate theropods. The formation is probably equivalent to the Grès supérieurs Formation of Laos, since animals like spinosaurids, sauropods, and derived ("advanced") iguanodontians have also been found there. In 2007, Milner and colleagues suggested that spinosaurids and iguanodontians may have spread from western to eastern Laurasia—the northern supercontinent at the time—during the Aptian, based on their distribution and presence in the Khok Kruat Formation. American palaeontologist Stephen Brusatte and colleagues noted in 2010 that the discovery of spinosaurids in Asia, a family previously known only from Europe, Africa, and South America, suggests a faunal interchange between Laurasia and Gondwana (in the south) during the early Late Cretaceous.
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M. crassus and M. sphenocerus holotypes Monoclonius was Edward Drinker Cope's third named ceratopsian, after Agathaumas and Polyonax. Several fossils were found by Cope, assisted by a young Charles Hazelius Sternberg, in the summer of 1876 near the Judith River in Chouteau County, Montana, only about a hundred miles (some 150 km) from the site of the Battle of the Little Bighorn, fought that June. The finds did not represent a single, let alone articulated, skeleton, but came from different locations. Together they included elements of most parts of the animal (only the feet were entirely missing), including the base part of a long nasal horn, part of the skull frill, brow horns, three fused cervical vertebrae, a sacrum, a shoulder girdle, an ilium, an ischium, two thighbones, a shinbone, a fibula and parts of a forelimb. Just two weeks after leaving Montana, Cope hastily described and named these finds on 30 October 1876 as the type species Monoclonius crassus.
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From elsewhere in the Dakangpu/Dawangzhangzi Beds, specimens have been discovered belonging to the birds Confuciusornis, Hongshanornis, Grabauornis, Liaoxiornis, Longicrusavis, Shanweiniao, Shenqiornis, and Zhongornis; the non-avialan theropod Sinosauropteryx; the ceratopsian Psittacosaurus; the pterosaur Cathayopterus; the lizards Dalinghosaurus and Yabeinosaurus; the choristoderes Hyphalosaurus and Monjurosuchus, of which the former is highly abundant; the turtle Manchurochelys; the mammals Acristatherium, Akidolestes, Chaoyangodens, Eomaia, Sinobaatar, and Sinodelphys; the frog Liaobatrachus; and fish, including Lycoptera (of which L. davidi is numerous), Peipiaosteus, and Protopsephurus. Environmentally, Jianianhualong lived in a lacustrine area, as evinced by the tuffaceous sandstone present throughout the Dawangzhangzi Beds. Like the rest of the Yixian Formation, the environment represented by these assemblages was seasonally semi-arid, with a low mean air temperature of . The local flora consists of a mixed assemblage of gymnosperms, such as Czekanowskia, Schizolepis, and the ephedroids Amphiephedra, Chengia, Ephedrites, and Liaoxia; and also early angiosperms, including Archaefructus, Hyrcantha (formerly Sinocarpus), Leefructus, and Potamogeton.
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Holotype skull shown in oblique, top, and right side views Since 2000, the Natural History Museum of Utah (UMNH) and the Bureau of Land Management have been conducting paleontological surveys of the Kaiparowits Formation at the Grand Staircase-Escalante National Monument in southern Utah. This national monument was established in 1996 in part for the preservation and study of its fossils, and the surveys there have yielded a wide array of unique dinosaur fossils. Field crews from other institutions have also participated, and the collaborative effort has been called the Kaiparowits Basin Project. Among the discoveries made were three new ceratopsian (horned dinosaur) taxa, one of which was identified from two localities (UMNH Locality VP 890 and 951) discovered by volunteer field crew member Scott Richardson during the field seasons of 2006 and 2007. It was preliminarily referred to as "Kaiparowits new taxon A" and identified as a chasmosaurine ceratopsid in a 2010 symposium book about ceratopsians.
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Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs Indiana University Press: Bloomington. pp. 319–347. . Variation in frill morphology; the top row are subadults, the rest are mature However, a newer study compared incidence rates of skull lesions in Triceratops and Centrosaurus and showed that these were consistent with Triceratops using its horns in combat and the frill being adapted as a protective structure, while lower pathology rates in Centrosaurus may indicate visual rather than physical use of cranial ornamentation, or a form of combat focused on the body rather than the head; as Centrosaurus was more closely related to Styracosaurus and both genera had long nasal horns, the results for this genus would be more applicable for Styracosaurus. The researchers also concluded that the damage found on the specimens in the study was often too localized to be caused by bone disease. The large frill on Styracosaurus and related genera also may have helped to increase body area to regulate body temperature, like the ears of the modern elephant.
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By the early 21st century, the prevailing theories were that the family was the sister group of either the Marginocephalia (which includes pachycephalosaurids and ceratopsians), or the Cerapoda (the former group plus ornithopods), or as one of the most basal radiations of ornithischians, before the split of the Genasauria (which includes the derived ornithischians). Heterodontosauridae was defined as a clade by Sereno in 1998 and 2005, and the group shares skull features such as three or fewer teeth in each premaxilla, caniniform teeth followed by a diastema, and a jugal horn below the eye. In 2006, palaeontologist Xu Xing and colleagues named the clade Heterodontosauriformes, which included Heterodontosauridae and Marginocephalia, since some features earlier only known from heterodontosaurs were also seen in the basal ceratopsian genus Yinlong. Timelapse video showing the construction of a model built around a skull cast, including musculature Many genera have been referred to Heterodontosauridae since the family was erected, yet Heterodontosaurus remains the most completely known genus, and has functioned as the primary reference point for the group in the palaeontological literature.
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45 percent of the postcranial skeleton was thought to be preserved, most of which was still under preparation by 2010. Assigned specimens include UMNH VP 16878, a skull of a subadult (between juvenile and adult) about half the size of the adult, missing the , , and predentary bones, and specimen UMNH VP 21339, a disarticulated subadult or adult. In all, four specimens were reportedly found. Map of where Kosmoceratops specimens (★) have been found within the Kaiparowits Formation (dark green) The describers of Kosmoceratops named the new chasmosaurine genera Utahceratops (also from the Kaiparowits Formation) and Vagaceratops (from the Dinosaur Park Formation, whose sole species, C. irvinensis, was formerly placed in Chasmosaurus) in the same article. These genera, which were considered unusual compared to typical members of their group, were part of a spate of ceratopsian discoveries in the early 21st century, when many new taxa were named (a 2013 study stated that half of all valid genera were named since 2003, and the decade has been called a "ceratopsid renaissance").
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