Chiromantes eulimene has a light brown carapace with light orange-yellow chelae. They can be distinguished from the closely related Parasesarma catenatum by the absence of fur around the hinges of the chelae.
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Laurantaeglyphea has five pairs of pereiopods, all without true chelae (claws).
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Beetle's claws on scanning electron microscope The scientifically correct term for the "claw" of an arthropod, such as a lobster or crab, is a chela (plural chelae). Legs bearing a chela are called chelipeds. Chelae are also called pincers.
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The chelae and other legs can be contracted into the entrance of the shell.
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The proximal ends of the leg joints are yellowish-brown and the distal parts brownish-black. The legs have short bristles on the inside and end in a claw. The front pair of legs are modified into chelae for gripping prey, although in this species, the chelae are relatively small.
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The whole body is covered in large tubercles, including the first pereiopods with their large chelae, and the other, smaller pereiopods.
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Uca pugnax, like other members of the family Ocypodidae, have chelae of different sizes: a large left chela and a small right chela. A chela (), also named claw, nipper, or pincer, is a pincer-like organ at the end of certain limbs of some arthropods. The name comes from Greek () through New Latin ('). The plural form is chelae.
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This squat lobster is an orange-red colour with white-tipped legs and chelae, pinkish lateral carapace spines and a paler ventral surface.
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The female of the species reaches up to 10 centimeters in length, while the male can exceed 15 centimeters. It is variable in color, sometimes with individuals of different colors occurring in one population, or even one litter. It may be reddish, black with reddish chelae, dark brown with yellowish legs and red chelae, or dark brown with reddish and black tail sections.
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Mithraculus sculptus is a small crab with a carapace longer than it is wide and large chelae (claws). The carapace is flat, shiny and green, finely sculpted, with whitish material adhering to the projections. The chelae are also green and are spoon-shaped and tipped with white. The walking legs are rather paler in colour and are hairy and often covered with encrustations.
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The stone crab's carapace is wide. They are brownish red with gray spots and a tan underside, and have large and unequally sized chelae (claws) with black tips. In addition to the usual sexual dimorphism exhibited by crabs, the female Florida stone crabs have a larger carapace than males of a similar age, and males generally have larger chelae than females.
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Legs bearing a chela are called chelipeds. Another name is claw because most chelae are curved and have a sharp point like a claw.
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Chelae or Chelai () was a coastal town of ancient Bithynia located on the Bosphorus. Its site is located near Keçili Liman in Asiatic Turkey.
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This crab could be confused with Glebocarcinus oregonensis which is a similar size, but that species has spiny ridges on the chelae instead of tubercles.
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Stone crabs have a hard exoskeleton shell which is brownish red with gray spots on top but a tan underside. They have two large and unequally-sized chelae (claws), which have black tips. The stone crab's carapace, or main shell, is and nearly wide. The males have a smaller carapace than females of a similar age, but males generally have larger chelae than females.
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This function is retained in the more basal Hughmilleriidae and Slimonidae, but pterygotid chelicerae were large and long with strong and well developed teeth on specialized chelae (claws).
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Stenopus spinosus can grow up to long, and is chiefly yellow, with white antennae and white tips to the chelae (claws). The uropods and telson have red tips.
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Porcelain crabs have large chelae (claws), which are used for territorial struggles, but not for catching food. The fifth pair of pereiopods is reduced and used for cleaning.
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Chelae or Chelai (), also called Philemporos, was a town of ancient Thrace on the Bosphorus, inhabited during Roman and Byzantine times. Its site is located near Bebek in European Turkey.
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The chelae (claws) are unequal: the right claw is stouter, and the left claw is narrower. The carapace is olive-green to brown, but the tips of the claws are black.
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Although Pilumnoides inglei resembles P. perlatus very closely, the carapace and chelae (claws) of P. inglei are smoother than in P. perlatus. The known adult specimens vary in size from to .
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The chelae are greenish-blue dorsally and the walking limbs are pale tan, both being dull orange ventrally. There is a blue spine with a yellow tip immediately behind the eye.
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Hottentotta conspersus can reach a length of . Body is sparsely hirsute, with granulated mesosoma and carapace and with seventh metasomal segment. Telson is granulated and very bulbous. Chelae are very narrow.
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Major characteristics include a soft leathery abdomen, a wide carapace narrowing at the anterior end much like a trapezoid, similar shaped chelae, and coloration ranging from a clouded green to reddish sometimes with banding along the legs. The name of this decapod is derived from the scale like pattern that covers its legs and partially covers its carapace. The odd structure of the chelae which are spoon-like in nature and are largely covered in setae.
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The forehead is low, excavated and depressed and of uniform height. Its pereiopods are fairly average and its chelae are without prominent, swollen protuberance on outer surface near the base of the fingers.
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N. hierichonticus can reach a length of . Its basic color ranges from a light brown or reddish-brown to dark brown. Its legs are yellowish. It has a thin metasoma and large pedipalps and chelae.
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The carapace of Petrolisthes armatus is roughly oval with a bluntly pointed front, and is granulated and covered with shallow, narrow ridges. P. armatus has two long chelipeds with chelae (pincers), three pairs of walking legs and a vestigial fourth pair. The chelipeds are composed of four rather than five segments and the chelae are long and have a distinctive orange spot that becomes visible when they are parted. The antennae, which have a spine on the first segment, are set outside the stalked eyes.
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Nephropsis atlantica is relatively small for a lobster, growing to a maximum total length of . The eyes are unpigmented, in contrast to shallow-water species, and the carapace, abdomen and chelae are covered in setae (bristles).
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Prior to 2005, the name Hemigrapsus penicillatus was used to cover animals that are now known to represent two distinct species. Hemigrapsus penicillatus (sensu stricto) has smaller patches of setae (bristles) on the chelae (claws) in males; Hemigrapsus takanoi has larger setal patches and larger coloured spots on the exoskeleton. It can be a variety of colors, including orange-brown, maroon, or green, with striped legs and spotted claws. Male brush-clawed shore crabs have a patch of light brown or yellow bristles (known as setae) on their chelae (pincers).
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The tailfan is U-shaped. The first cheliped is smooth and distinctly longer than the other legs. The species is sexually dimorphic, with males having significantly larger chelae than females while females have broader abdomens. Coloration varies among populations.
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Kovarikia, is a genus of scorpion belonging to the family Scorpionidae. All described species are restricted to humid rocky microhabitats of southern California. Three species identified. Major identification is from unique neobothriotaxy found on the ventral surface of the pedipalp chelae.
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Adult specimens reach a considerable size of about 70 mm. The overall color is uniformly yellow to yellow-reddish with darker carinae on the metasoma. The scorpion shows the typical characteristics of the genus Androctonus including slender pedipalp chelae and a thick, robust metasoma with a proportionally large vesicle (bulbous part of telson containing the venom glands). Granulation of the cephalothorax and mesosoma is slightly more pronounced in the male than in the female and the males have an excavation at the base of the fixed finger of the chelae to accommodate the females pincers during mating "dance".
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Calappa hepatica grows to a carapace width of about ; the length is always less than two thirds of its width. The posterior portion of the shell has broad extensions with several blunt teeth on the margin, and these largely conceal the walking legs. The carapace and the exposed parts of the chelae (pincers) are a mottled greyish-brown colour, and are covered with small raised tubercles of various sizes, making the crabs well-camouflaged when semi-submerged in the sand. The chelae are large and powerful, and specially adapted to the crab's feeding behaviour, the crushing and eating of molluscs.
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The eastern swamp crayfish (Gramastacus lacus) is a species of small freshwater crayfish from coastal New South Wales, Australia. It is distinguished from related species by large genital papilla on the males, large raised postorbital ridges, a laterally compressed carapace, and elongated chelae.
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It is unable to feed itself with its chelae and uses the tentacles of the anemones to collect food particles which it then removes with its mobile maxillipeds. The red eggs of Lybia tessellata are carried around on the female's abdomen where they are brooded.
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He had been brought specimens by J. Caldwell, and described them in 1865 under the name Astacus Caldwelli Bate, 1865. By the end of the 19th century, scientists had settled on the name Astacus madagascarensis, treating the others as synonyms, and to preserve nomenclatural stability, the name A. goudotii was suppressed by the International Commission on Zoological Nomenclature in 1958. The next new taxon to be described was the variety betsileoensis described by Georges Petit in 1923. In 1927, he divided the Malagasy crayfish into the "macrophthalmes", with large eyes, a convex carapace and flattened chelae, and the "microphthalmes", with small eyes, cylindrical carapace and more robust chelae.
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When it is disturbed, it folds its chelae (pincers) in front of its face and retracts its walking legs, forming a compact, well-armoured box-like structure; this defensive stance makes it appear to be embarrassed, and has led to its receiving the name, "shame-faced crab".
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A short spine above the eye and the angled articulation of the second chelae with the carpus differentiate the California freshwater shrimp from other shrimp that occur California. A carapace length (reckoned from eye socket to tail-tip) of slightly more than five centimeters can be attained.
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The spotted cleaner shrimp grows to a length of about . It has a transparent body patterned with brown and white saddle shaped markings. The chelae and legs are boldly striped in red, purple and white. There are two pairs of long white antennae banded in black.
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The carapace is flattened and covered in short fine hairs, length up to 12mm, width up to 12.5mm. Males appear dull reddish to tan brown, while females are greyish brown, often with small red spots. Chelae more slender than in P. elongatus, generally larger in the male.
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Crambeidae is a family of marine demosponges.Register of Marine Species Identification of members of this family of sponges is based on microscopic examination of the spicules in their skeleton. The megascleres consist of peripheral thinner subtylostyles and thicker choanosomal styles while the microscleres are exclusively anchorate chelae.
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C. haematocheir has a square carapace with a smooth surface and irregular stripes along the sides. Males have large, smooth chelae with curved claws. The color of these crabs varies throughout their development; juvenile crabs typically have a white or yellow carapace, while adults are usually crimson red.
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Small to moderately sized scorpions (40–75 mm). Most species are yellow, some are brownish, yellow-grayish or yellow-greenish colored. They show a rather slim habitus with long walking legs and a slender metasoma; pedipalp chelae very gracile and elongate. Cephalothorax smooth or with very weak carinae.
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Palinurus elephas is a related species from the north-east Atlantic Ocean. The total length of Palinurus charlestoni can reach , with the average size around .Holthuis (1991) Like other spiny lobsters, it has five pairs of pereiopods (walking legs), but no chelae (claws).Forest & Postel (1964), p. 105.
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P. fortis is thick and stocky, with relatively heavy chelae. It is usually dark brown dorsally with bright orange areas on its underside. It grows about 2-4 inches long. It lives in cold, clear, rocky areas of the mountain rivers, and feeds on the slime coating the rocks.
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The family Pandalidae is a taxon of caridean shrimp. These species are commonly called pandalid shrimp. They are edible and have high economic value. They are characterised by the subdivided carpus of the second pereiopod and, mainly, by the lack of the chelae (claws) on the first pereiopod.
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Two disjointed claws were collected from the same horizon as the holotype. It is not clear that they came from the same animal as the holotype. The two isolated chelae also differ from each other, although this could be due to sexual dimorphism or ontogenetic differences rather than differences between species.
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Their antennae lack a scaphocerite, the flattened exopod of the antenna. This is fused to the epistome (a plate between the labrum and the basis of the antenna). The flagellum, at the top of the antenna, is stout, tapering, and very long. The ambulatory legs (pereopods) end in claws (chelae).
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Juxtastenopus grows to a total body length of long (carapace length: ). In life, the animals are red or pinkish, but with white tips to the chelae (claws) on the enlarged third pereiopods (walking legs). Females are reproductive at lengths around , and carry between 27 and 132 eggs, each initially in diameter.
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M. carcinus is omnivorous, with a diet consisting of molluscs, small fish, algae, leaf litter and insects. M. carcinus has a tan or yellow body with dark brown stripes. Its chelae are unusually long and thin, to facilitate foraging for food in small crevices, and may be blue or green in colour.
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Calappa is a genus of crabs known commonly as box crabs or shame-faced crabs. The name box crab comes from their distinctly bulky carapace, and the name shame-faced is from anthropomorphising the way the crab's chelae (claws) fold up and cover its face, as if it were hiding its face in shame.
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Coloration may be considerable variable between individuals of the same species or among regional populations. They show a typical buthid habitus with gracile pedipalp chelae and a moderately thickened metasoma. The vesicle is bulbous and proportionally large in some species. The cephalothorax and mesosoma shows distinct granulation in most species, some are strongly hirsute.
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When another organism attempts to eat or steal its sponge, the host crab attacks with its chelae. When concealed within a mass of other sponges, the crab is able to identify the sponge it most recently claimed. In addition, it surpasses considerable physical challenges, such as lifting rocks, in order to retrieve its sponge.
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The Dougherty Plain cave crayfish grows to a length of about with antennae twice this length. It is a colourless species with unpigmented eyes, segmented cephalothorax and abdomen, a pair of slender chelae (claws) with a row or two of tubercles and long slender appendages. The rostrum is long and unadorned with tubercles or spines.
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Chelate or sub-chelate (pincer-like) pedipalps are found in several arachnid groups (Ricinulei, Thelyphonida, scorpions and pseudoscorpions) but the chelae in most of these groups may not be homologous with those found in Xiphosura. The pedipalps are distinctly raptorial (i.e., modified for seizing prey) in the Amblypygi, Thelyphonida, Schizomida, and some Opiliones belonging to the laniatorid group.
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The legs are long and bear spines which may help the crab cling onto the kelp. The colour of this crab varies, usually being brown, red or yellow, but sometimes being orange, pink, white or blue. The chelae (claws) have blue extremities, with red, orange or white tips, and the walking legs often have pale bands.
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The name "Achelata" derives from the fact that all the members of this group lack the chelae (claws) that are found on almost all other decapods (from the Greek , ' = "not", , chela = "claw"). They are further united by the great enlargement of the first antennae, by the special "phyllosoma" form of the larva, and by a number of other characters.
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Its carapace is coloured bright red, with circular and elongated whitish patches. Its rostrum is red and its orbital hoods transparent. The antennal and antennular peduncles are reddish, while both flagella are purplish red. Its major and minor chelipeds are red; the merus showing a distal white patch; chelae are deep red, white on the tips of fingers.
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Chelae or Chelai () was a coastal town of ancient Bithynia located on the Pontus Euxinus. It appears in the Tabula Peutingeriana, and in the Periplus Ponti Euxini written by Arrian, who places it 20 stadia east of Thynias and 180 west of the mouth of the Sangarius River. Its site is located near Cebice in Asiatic Turkey.
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The pedipalps of M. eupeus have a maximum of ten diagonal rows of granules on the fixed finger and eleven on the movable finger. The pedipalp chelae (pincers) are wider than the patella (segment IV). The segments of the metasoma are thick and have eight keels (octocarinate). The telson is subglobose with a flat dorsal surface.
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Up to 9 cm (3.5 in) long, it is variable in appearance; all black in northern KwaZulu-Natal and brown with yellow legs in Mpumalanga. The legs are otherwise rust-coloured. It has a heavy-set body with stocky legs and stout arms (pedipalps) with short pincers (chelae). Its cephalothorax around 11 mm long and broader (11.5 mm) across.
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Although the extant species are all restricted to deep waters, the group is thought to have originated in shallow water. Over time, the eyes have reduced in size to the vestigial state seen in extant Polychelidae, the body has narrowed, and the chelae have become less robust; among extant taxa, the most plesiomorphic state is seen in Willemoesia.
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The Astacidea are distinguished from most other decapods by the presence of chelae (claws) on each of the first three pairs of pereiopods (walking legs), the first of which is much larger than the remaining two pairs. The last two pairs of pereiopods are simple (without claws), except in Thaumastocheles, where the fifth pereiopod may have "a minute pincer".
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Its carapace, or upper shell, is flat, circular, and rough with arched lateral margins, and may be up to 37 mm in length. Its chelae, or claws, are short, small, and flattened. Its pereiopods, or legs, are long with a tapered end. The margin of the inferior extremity of its last pair of legs is serrate.
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Population of Kiwa around a hydrothermal vent Unlike Kiwa hirsuta and Kiwa puravida, which are notable for having a dense covering of setae on their elongated chelae, this species has shorter chelae, with most of the setae concentrated instead on the ventral surface of the crab. Filamentous bacteria were found on the setae and similar-looking sulfur-oxidising bacteria have been found amongst the setae of Kiwa hirsuta and Kiwa puravida. It has been hypothesised that these sulfur-oxidising bacteria, which fix carbon from the water by oxidising sulfides in the hydrothermal fluid, are a significant source of nutrition to the crabs. The Hoff crabs were found living adjacent to and on the sides of hydrothermal vent chimneys living in close proximity to fluid emanating from the chimneys at temperatures greater than of .
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The Achaeus spinosus carapace has an oval shape and does not exceed in length. This crab possesses long fine clawless legs, except the front pair which is smaller and bears chelae (pincers). The pedunculate eyes are red. The whole whitish body is thickly covered with fine hairs which help to fix some pieces of sponge or fixed hydroids for camouflage.
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The knot- fingered mud crab is a small crab with unequal-sized chelae. The larger one is particularly broad and has teeth in the "molar area" and an immobile finger. Often this claw is worn and coalesced. The carapace and upper side of the limbs are a dull mottled reddish colour while the undersides of the body and limbs are whitish.
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The carapace of this hermit crab can grow to a length of about . The rostrum is pointed and there is a spine at the tip of the small eye scale. The eye stalks are long and cylindrical and the antennal scales are thorny and nearly cover the bases of the antennae. The chelae (claws) are granulated and covered with short hairs.
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The enlarged pedipalps have raised ridges along the femur, patella, and the chelae. There are trichobothria present but the exact configuration is hard to determine due to the preservation. Both the fixed and mobile sides of the chela have rows of teeth with a slightly darkened coloration. The underside of the mesosoma clearly shows the paired pecten combs each with twenty-nine teeth.
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Its ocelli (light-sensitive simple eyes) were very small and located centrally. As in most eurypterid groups, the chelae (pincers) were small. It differs from other species in the more convergent form of the carapace and in the large size of the eyes, which were furthest from the margin. This species reached a length of 8 cm (3.1 in) in total.
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It uses its chelae alternately, gathering a polyp with one claw while it feeds on a polyp held in the other. It has been observed to gather and consume ten polyps in a minute. It also feeds on organisms encrusting the leaf blades of turtle grass (Thalassia testudinum). When threatened it often hides beneath the extended tentacles of the sun anemone (Stichodactyla helianthus).
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The genus Ctenocheloides is known from a single female specimen. The total length of the specimen is , with a carapace long. Ctenocheloides resembles the genus Ctenocheles, as reflected in the name of the genus, both genera having pectinate (comb-like) fingers to the chelae (claws). Ctenocheloides differs from Ctenocheles in having no rostrum, having well-developed eyes, and in having shorter, fatter claws.
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The animals grouped into the infraorder Polychelida are united by the presence of at least four pairs of chelae (claws). Five families are included, all but one of which are extinct. The 38 extant species are all in the family Polychelidae. The group has a fossil record stretching back to the Upper Triassic, and had its peak diversity in the Mesozoic.
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In the pterygotids, the chelicerae were large and long, with strong well developed teeth on specialised chelae (claws). These specialised chelicerae, likely used for prey capture but differing in the exact role from genus to genus, are also the primary feature that distinguishes members of the group from eurypterids of the other pterygotioid families, Slimonidae and Hughmilleriidae, and other eurypterids in general.
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Decapods can have as many as 38 appendages, arranged in one pair per body segment. As the name Decapoda (from the Greek , ', "ten", and , -pod, "foot") implies, ten of these appendages are considered legs. They are the pereiopods, found on the last five thoracic segments. In many decapods, one pair of these "legs" has enlarged pincers, called chelae, with the legs being called chelipeds.
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M. novaezelandieae hunts by using its powerful chelae to catch, kill, crush and access its prey, then feeds using its mouthparts. Its claws are capable of breaking open the tough shells of molluscs allowing the crab to reach the soft mollusc body inside and feed on it. Its claws allow it to effectively kill other forms of prey such as crustaceans as well.Cresswell, P. (1988).
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Grapsus grapsus is a typically shaped crab, with five pairs of legs, the front two bearing small, blocky, symmetrical chelae (claws). The other legs are broad and flat, with only the tips touching the substrate. The crab's round, flat carapace is slightly longer than . Young G. grapsus are black or dark brown in colour and are camouflaged well on the black lava coasts of volcanic islands.
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Drew et al. (2010), p. 49 The carapace may reach a length of , and a width up to .Drew et al. (2010), p. 46 The body of the coconut crab is, like that of all decapods, divided into a front section (cephalothorax), which has 10 legs, and an abdomen. The front-most pair of legs has large chelae (claws), with the left being larger than the right.
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The C. maenas is a crustacean and has many typical crustacean traits, including, a hard shell, 8 legs, 2 claws (also known as chelae), and 2 eyes. Almost all of these traits are shared throughout the crustacean family and it all applies to the C. maenas. Each of the traits is very useful for underwater living. The shell is used for protection if the crab is attacked.
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The rostrum is a greenish-blue, and the pleon is dark blue or black, with pinkish-grey or cream coloration on the margins (in some individuals the pleon is greenish-grey with pink speckles). The tail fan is cream-colored or pink around the outside margin. The legs are blue, and the chelae are blue with varying intensities, with cream-colored or white margins.
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Carcinocorini are a tribe of ambush bugs which are distinct in have a claw- like modification of the foreleg used to capture their prey. Such claw or chelae, which are common in crabs, are almost unknown in insects, present only in female wasps of the family Dryinidae. The name of the tribe is derived from the Greek karkinos for crab and coris for bug.
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In addition to fighting over mates and food, P. longicarpus will fight over shells. Larger crabs or crabs with less suitable shells will often forcibly remove other crabs with more desirable shells by clasping the chelae, or legs, of the occupant with its pincers, which allows them to takeover the desired shell. Along with predation, shell availability is a major factor in determining P. longicarpus population size.
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The antennules have a third segments 1.5 to 2.5 times as longer as the first and second together. The maxilla has distinctly separated coxae and bases. The first pair of pereopods is very unequal in size, especially in adult males, presenting a uniquely bold instance sexual dimorphism in the genus. The second pair is well chelated, but the fourth and fifth have rather imperfect chelae.
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Metanephrops challengeri is a slender lobster, typically long, but exceptionally up to , and weighing up to each. Its chelipeds (legs bearing the main chelae, or claws) are long, narrow, and slightly unequal. The second and third pairs of pereiopods also end in small claws, but the fourth and fifth pairs do not. The carapace is smooth, and extends forwards into a long, narrow rostrum, only slightly shorter than the carapace.
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Adult specimens of Heterometrus bengalensis grow to a length of 95 to 115 millimeters and a dark reddish-brown to light-brown body color. The combs of the pecten organ have 14 to 17 teeth in both sexes. The chela, femora, and patella of the pedipalps are narrower and longer in the males than in the females. The surfaces of the chelae are uneven, but without pronounced granules and keels.
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The pterygotid telsons were flattened and expanded, likely used as rudders when swimming. Their walking legs were small and slender, without spines, and they were likely not capable of walking on land. Pterygotus is distinguishable from other pterygotids by the curved distal margin of the chelae (claws). The prosoma (head) is subtrapezoidal (a trapezoid with rounded corners), with compound eyes located near the edge of the front corners.
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Several different species of branchiobdellid are sometimes found on a single crayfish. Their hosts include open-water crustaceans, cave-dwellers and burrowers, but many branchiobdellids have a very limited range, occurring in a single river system or a single cave. An Appalachian brook crayfish was found to have one species of branchiobdellid in the gill chambers, one on the oral and ventral surfaces of the body and one on the chelae.
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The dorsal parts of the thorax and abdomen will often be light brown, green, tan, or steel blue and patterned with red or cream-colored spots. The cephalon is usually black or brown on the dorsal surface, with lighter toned blue highlights on the lateral edges. The body's ventral surface is cream-colored or transparent. The first chelae are black to dark blue, with bright blue coloration along the edges and red joints.
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Like other spiny lobsters, Panulirus echinatus has no pincer-like chelae on its front walking legs. It differs from related species by having just two large spines on the antennular plate, just in front of the carapace, and the exopod of the third feeding appendage is reduced and bears no flagellum. The basic colour is brown with large white rounded spots. The antennules and limbs are brown and have longitudinal white or yellow markings.
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Mouthparts and chelae of a female In the Carantec The carapace of C. pagurus adults is a reddish-brown colour, while in young specimens it is purple-brown. It occasionally bears white patches, and is shaped along the front edge into nine rounded lobes, resembling a pie crust. Males typically have a carapace long, and females long, although they may reach up to long in exceptional cases. Carapace width is typically , or exceptionally up to .
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P. hirtellus is a small crab, with a carapace up to wide and long. The carapace and legs are reddish brown or purple, with the inner surfaces of the legs orange or paler. Both the carapace and the walking legs have a dense covering of setae. The first pair of legs bear large chelae (claws), of which one, usually the right claw, is larger than the other, and the fingers of both claws are brown.
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Koura use their chelae for both attack and defence, and when one limb is lost, the koura will divert energy for overall growth to restoring the lost limb. The only disease known to seriously affect koura is "white tail disease" caused by the microsporidian parasite Thelohania contejeani. This parasite causes degeneration of striated muscle in the tail area, which turns the tail a pale white colour and correspondingly leads to death soon after.
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The Chessmen of Mars introduces the Kaldanes of Bantoom. Their form is almost all head but for six spiderlike legs and a pair of chelae. Their racial goal is to evolve towards pure intellect and away from bodily existence. In order to function in the physical realm, they have bred the Rykors, a complementary species composed of a body similar to that of a perfect specimen of Red Martian but lacking a head.
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Lauridromia dehaani can be found subtidally and on mudflats uncovered at low tide. It probably feeds on fragments of algae and other vegetation. It searches out a sponge, often a species of Suberites, and uses its chelae to fashion a piece to the approximate size of its carapace, and then moulds this in place. It will carefully cut a piece of sponge growing on a rock or remove some from the surface of a shell.
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L. tessellata is a small crab growing to a width of about . The carapace is trapezoid in shape and the margin has a distinct tooth-shaped projection on either side, just behind the short-stalked eye. The surface of the carapace is marked into several differently coloured, geometric regions by a network of dark lines giving it the appearance of stained glass. The chelipeds do not have the broad chelae (claws) typical of decapod crabs.
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Kisatchie painted crawfish are brown or olive with red, blue, and white to yellow markings. The red is mainly on the central joints of the pereiopods, the postorbital ridges, and a little on the posterior margins of the uropods (tail fins) and abdominal segments. The fingers of the long, stout chelae (claws) are in order from tip to base, red, yellow/cream, blue, and greenish brown/brown. Its cephalothorax is about long, to a maximum of .
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Its carapace is coloured mostly yellow-orange, with three white patches laterally. Its rostrum is reddish-orange and its orbital hoods translucent. The antennal and antennular peduncles are orange-red, while its mouthparts are mostly found to be colourless, except for the palp and caridean lobe of its first maxilliped, which are reddish. Its major and minor chelipeds are orange-red; the merus showing a distal white patch; chelae almost white on the tips of fingers.
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Specimens of Neobisiidae have two very long pedipalps with palpal chelae (pincers) which strongly resemble the pincers found on true scorpions. The pedipalps consists of an immobile "hand" and "finger", with a separate movable finger controlled by an adductor muscle. Contrary to most other pseudoscorpions a venom gland and duct are located in the immobile "finger" part of each pedipalp, rather than in the movable one. The venom is used to capture and immobilize the prey.
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They were equipped with small pincers used to manipulate food fragments and push them into the mouth. In one lineage, the Pterygotidae, the chelicerae were large and long, with strong, well-developed teeth on specialised chelae (claws). The subsequent pairs of appendages, numbers II to VI, possessed gnathobases (or "tooth-plates") on the coxae (limb segments) used for feeding. These appendages were generally walking legs that were cylindrical in shape and were covered in spines in some species.
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Pagurus acadianus was first identified in scientific literature by scientist J.E. Benedict in 1901. As examined by Morris H. Roberts, Jr.’s, Benedict was able to differentiate this organism from that of a very similar taxa, Pagurus benhardus, due to physical variations. Benedict observed that Pagurus acadianus had larger eyestalks, shorter fingers of the chelae and sharper chelipeds, all of which are necessary identifiers of the Acadian hermit crab. Taxonomically, the Acadian hermit crab belongs to the Arthropoda phyla.
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Gecarcinus quadratus, a land crab from Central America Crabs are generally covered with a thick exoskeleton, composed primarily of highly mineralized chitin, and armed with a single pair of chelae (claws). Crabs are found in all of the world's oceans, while many crabs live in fresh water and on land, particularly in tropical regions. Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span up to .
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The holotype of M. bahamaensis has a total length (TL) of (carapace length, CL, ); the paratype is smaller at TL , CL . In common with other troglobitic species, the body lacks pigments, and the eyes are vestigial. Like other stenopodideans, Macromaxillocaris has chelae (claws) on the first three pairs of pereiopods (walking legs); it differs from them by the size of the third maxilliped, which is greatly enlarged in Macromaxillocaris, and is the strongest of all the animal's appendages.
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Belzebub is a genus of prawns in the family Luciferidae. The species which make up the genus Belzebub were formerly placed in the genus Lucifer but were separated to form Belzebub after a cladistic analysis. They are very small planktonic and benthic prawns with an extreme lateral compression of the carapace with elongated mandibles and anteriors of the pereiopods but lacking pereiopods 4 and 5 and any gills. The pereiopods either lack chelae or they are substantially reduced.
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Males of this species grow to a total length of about with a carapace length of while females may attain a total length of . Like other rock lobsters, it lacks chelae (claws) on its front pair of walking legs. The carapace is armoured with large flat spines, about as wide as they are long, mixed with small spines. The first few abdominal segments are sculptured with fine transverse grooves at the front of each segment with a smoother area behind.
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Its surface is rough, with scattered tubercles, and is divided into distinct regions by a series of grooves. A raised ridge runs sinuously along the front of the carapace, interrupted by a groove in the centre and by grooves towards each side of the carapace. The colour of Seychellum is described as "'" ("dark yellow, which becomes quite brown in the anterior part of the carapace"). The antennae are minute (smaller than those of Deckenia), and the chelae (claws) are unequal in size.
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Anteon caledonianum Anteon is the largest genus in the subfamily Anteoninae of the family Dryinidae, it occurs globally and there is a current total of 423 species described. The species in the genus Anteon are parasitoids of leafhoppers from the family Cicadellidae. The female wasps of the family Dryinidae almost always possess a chelate protarsus, as do females of species within Anteon. The chelae are used to capture and immobilise the host leafhopper to allow the wasp to oviposit and feed on it.
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The second segment of a carideans overlaps both the first and the third segment, while the second segment of a dendrobranchiate overlaps only the third segment. They also differ in that carideans typically have two pairs of chelae (claws), while dendrobranchiates have three. A third group, the Stenopodidea, contains around 70 species and differs from the other groups in that the third pairs of legs is greatly enlarged. Procarididea are the sister group to the Caridea, comprising only eleven species.
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Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata, P: 30–31. Acutiramus is classified as part of the eurypterid family Pterygotidae, a family differentiated from other eurypterids by their flattened telsons (the most posterior segment of the body) and their modified chelicerae (frontal appendages), ending in well- developed chelae (claws). Many pterygotid eurypterids, such as Jaekelopterus and Pterygotus, grew to gigantic proportions. Acutiramus was no exception, with the largest species, A. bohemicus, surpassing 2 metres (6.6 ft) in length.
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The appendages of males are slender and covered with dense long yellow curving hairs interspersed with shorter and finer hairs. The claw-bearing legs (chelipeds, the first pereiopod pair) are much longer and somewhat elongated in males than they are in females. Male chelipeds grow to a length of about with the claws (chelae) making up . The arm (merus) of the chelipeds has two rows of spines on the inner margins, longer on the lower margin than on the upper margin.
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Sphaerotheriidans are characterized by a relatively conservative body morphology; superficially all species and genera look the same. Dorsally, their head is followed by twelve body tergites (collum, thoracic shield, and ten normal tergites) and the anal shield. Ventrally, females possess twenty-one leg pairs (forty-two legs in total), while males carry two additional modified leg pairs, the anterior and posterior telopods under their anal shield. The telopods resemble chelae and/or clamp-like structures, which are probably used in holding the female during mating.
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Like other sesarmid crabs, P. pictum has a square carapace. Its chelae are covered with scaly tubercles that wear down as the crab ages, and some short setae (hairs). The inside of the claw of the crab is smooth, although many ridges and fine granules are present on the movable portion; these ridges and granules are smaller in female and juvenile crabs than in adult males. The top portion (merus) of the walking legs of this crab are broad relative to the lower limb.
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The red reef hermit crab grows to a length of about . The limbs and chelae (pincers) are smooth and hairless, and the left chela is slightly larger than the right one; the abdomen is unarmoured and is concealed in the recesses of the gastropod mollusc shell that protects it. The general colour of this hermit crab is bright red with the exception of the antennae, which are deep red, and the elongated eyestalks, which are yellow or yellowish-orange. The corneas of the eyes are yellowish-green.
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Leptograpsus variegatus is an omnivore and will eat a broad range of plant and animal life. While the crab may eat algae growing on rocks (such as Corallina and Ulva lactuca), they have also been observed feeding on barnacles and limpets. The crab captures limpets by quickly placing their chelae under the limpets shell when it begins to move and then flips it over. Notably, there is also a single observation of this species preying upon a Raukawa gecko, which is native to New Zealand.
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Pagurus dalli has a smooth, partially calcified carapace up to long, and a curved abdomen. The legs are light tan with white stripes, and it is the broad white band on the merus segment of the chelae (claws) that gives this hermit crab its common name. The dorsal surface of the carapace has a network of white, red, light and dark brown markings and is rimmed with red, and the flagellae (terminal segments) of the second pair of antennae are reddish-brown and white.
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The majority of branchiobdellids use crayfish as hosts, usually living on their heads, carapaces and chelae (claws), but in some instances living inside their gill cavities. In East Asia, some species live on freshwater shrimp, and in Northern and Central America, freshwater crabs, shrimps and isopods host branchiobdellids, and some have even been found on Chesapeake blue crabs. In the Euro/Mediterranean region, however, crayfish are exclusively used as hosts. Some branchiobdellids are generalists, but a few are limited to association with a single host species.
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The crab's front limbs have modified chelae, each of which can gently grip a sea anemone by its column, and it usually holds one in each claw. The living anemone is brandished like a weapon to keep predators away and is also used in ritualistic territorial protection. The sea anemones used are small and seldom exceed a column height of . If it loses one of its anemones, the crab can tear the other one in half, after which each part grows into a new individual.
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Geograpsus lividus can reach a width of about .CBRAT - Coastal Biodiversity Risk Analysis ToolJac Forest,Carel von Vaupel Klein Treatise on Zoology - Anatomy, Taxonomy, Biology. The Crustacea, Volume 3 Cephalothorax is globose, smooth and without tubercles.Jose A. Cuesta, Guillermo Guerao, Christoph D. Schubart, Klaus Anger Morphology and growth of the larval stages of Geograpsus lividus (Crustacea, Brachyura), with the descriptions of new larval characters for the Grapsidae and an undescribed setation pattern in extended developments Chelar tubercles are restricted to the upper half of the chelae.
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Dryinus grimaldii females ranges in size from with an overall body coloration thought to have been brick-red to brownish-yellow. The chelae on the front pair of legs are modified into claws each with a pair of teeth just below the claw apex. The morphology of the claw is a key distinguishing feature between D. grimaldii and D. rasnitsyni, which has a much more spatulate shaped claw then that of D. grimaldii. The antennae of D. grimaldii are notably long, being over nine times the length of the head, with a filiform morphology.
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Clarke, J. K., Ruedemann R. (1912) "The Eurypterida of New York" Acutiramus can be distinguished from other pterygotids by the distal margin of the chelae (pincers), where the final tooth is at an acute angle relative to the rest of the claw. The large tooth in the center of the claw is distally inclined (points forwards). The prosoma (head) is subquadrate (nearly square-shaped), with compound eyes located at the edge of the front corners. The telson (the posteriormost segment of its body) has a low row of knobs running down its center.
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Two similar but undescribed species are known from vents on the South West Indian Ridge and at the Galápagos respectively. Analysis of DNA has confirmed the distinction of the species, them having diverged from each other millions of years ago. The third undescribed species of Kiwa was discovered in 2010 in the Atlantic sector of the Southern Ocean at vents on the East Scotia Ridge. Compared with the first two species, it has proportionally much shorter chelae, with the majority of the bacteria-growing setae concentrated on the ventral carapace.
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The animal's mouthparts comprise paired mandibles, maxillules, maxillae and three pairs of maxillipeds, although the third maxillipeds are very long and more closely resemble the walking legs than the other mouthparts. There are five pairs of walking legs, or pereiopods, diminishing in size from front to back. There are no chelae (claws), although the last segment may be able to grip against an extension of the previous segment in some cases (subchelate). The first four pairs are similarly arranged, extending forwards and downwards to be used in walking; the fifth pair is directed upwards.
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It is yellowish-brown, except for the tips of the chelae, which are black. X. hydrophilus closely resembles X. pilipes, from which it can be distinguished by the absence of fringes of setae on the second to fifth pairs of pereiopods (walking legs). Other key identification features are that the second to fourthth pairs of antero- lateral lobes are separated from each other by an inward pointing, wide and shallow depression, the postero-lateral margins of the carapace are bristly and the inner surfaces of the propodus has a broad, longitudinal pitted cavity.
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The head of an ant: Chitin reinforced with sclerotisation This female Pandinus scorpion Has heavily sclerotised chelae, tail and dorsum, but has flexible lateral areas to allow for expansion when gravid Arthropods are covered with a tough, resilient integument or exoskeleton of chitin. Generally the exoskeleton will have thickened areas in which the chitin is reinforced or stiffened by materials such as minerals or hardened proteins. This happens in parts of the body where there is a need for rigidity or elasticity. Typically the mineral crystals, mainly calcium carbonate, are deposited among the chitin and protein molecules in a process called biomineralization.
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Operculum with type A genital appendage of H. suecicus Holmipterus was a large eurypterid, with some paratypes indicating a size of even 1.5 m (4.9 ft). It had characteristics that allow it to differentiate itself from all the eurypterids. The chelicerae (frontal appendages) had four joints, with a long, narrow and falcate (with a curvature similar to that of the sickle) chelae (claws) of 12.4 mm (0.49 in) long. The hand was about as broad as long, with a socket for the articulation of the condyle (round prominence at the end of a bone) of the 4th joint.
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Erettopterus is classified as part of the eurypterid family Pterygotidae, a family differentiated from other eurypterids by their flattened telsons (the most posterior segment of the body) and their modified chelicerae (frontal appendages), ending in well-developed chelae (claws). Although some pterygotid eurypterids, such as Jaekelopterus or Acutiramus grew to gigantic proportions, it is estimated that the largest species of Erettopterus, E. osiliensis, reached . Erettopterus had a bilobed (divided into two lobes) telson, which is its main characteristic. The forms of chelicerae are very diverse between species, but they are generally very long with small curved teeth without serrations.
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The graceful rock crab or slender crab, Metacarcinus gracilis (the naming convention recognized by WoRMS) or Cancer gracilis (the naming convention recognized by ITIS), is one of only two members of the genus Metacarcinus, recognized by WoRMS, whose chelae (claws) are white tipped, the other crab being M. magister (Dungeness crab). Both of these eastern Pacific crab species are recognized by ITIS as belonging to the much larger genus Cancer. M. gracilis has been caught from Alaska to Bahía Magdelena, Baja California. Although M. gracilis is only found in the Pacific Ocean, it has cousins in the Atlantic Ocean.
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Fossil of A. cummingsi (left) and Eurypterus remipes, Schiele Museum of Natural History, North Carolina.Clarke and Ruedemann noted in 1912 that P. macrophthalmus was easily distinguished from other species of Pterygotus. While it was obviously closely related to P. anglicus based on features of the telson, the two species could easily be differentiated by several characteristics, notably the fishhook-like shape of the teeth of the chelae (claws) and the direction they pointed in being different. These features of the claw were noted as being similar to those of P. osiliensis, a species with a highly distinct bilobed telson.
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Dryinus rasnitsyni females are in total length with an overall body coloration thought to have been brown, though the head, chela, and palpi were a brick-red to brownish-yellow. The species is macropterous, with fore wings that are clear with a very slight darkening away from hyaline and hind-wings that are fully darkened. The chelae on the front pair of legs are modified into claws each with a pair of teeth just below the claw apex. The morphology of the claw is a key distinguishing feature between D. grimaldii and D. rasnitsyni, which has a much more spatulate shaped claw then that of D. grimaldii.
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Planes minutus is a small crab, reaching a maximum carapace length of , and typically less than . It has conspicuous eyes in wide orbits at the corners of the wide front edge of the carapace. The first pair of pereiopods (walking legs) bear a symmetrical pair of chelae with cutting teeth; the other four pairs are adorned with spines on the last two segments of each leg. It differs from the larger P. major in that males have a broadly triangular abdomen, rather than one which narrows abruptly after the third segment, and from P. marinus in having flattened legs with a fringe of setae that aid in swimming.
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The next two pairs, as with other hermit crabs, are large, powerful walking legs with pointed tips, which allow coconut crabs to climb vertical or overhanging surfaces. The fourth pair of legs is smaller with tweezer-like chelae at the end, allowing young coconut crabs to grip the inside of a shell or coconut husk to carry for protection; adults use this pair for walking and climbing. The last pair of legs is very small and is used by females to tend their eggs, and by the males in mating. This last pair of legs is usually held inside the carapace, in the cavity containing the breathing organs.
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Commercially important species include two species of Homarus (which looks more like the stereotypical lobster) from the northern Atlantic Ocean, and scampi (which looks more like a shrimp, or a "mini lobster") – the Northern Hemisphere genus Nephrops and the Southern Hemisphere genus Metanephrops. Although several other groups of crustaceans have the word "lobster" in their names, the unqualified term "lobster" generally refers to the clawed lobsters of the family Nephropidae. Clawed lobsters are not closely related to spiny lobsters or slipper lobsters, which have no claws (chelae), or to squat lobsters. The closest living relatives of clawed lobsters are the reef lobsters and the three families of freshwater crayfish.
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The teeth on the chelae fingers of Erettopterus were mostly short and suitable for holding prey, and could have effectively sliced up the prey. The number of lenses in the compound eyes of Erettopterus is comparable to the number in Pterygotus and Jaekelopterus which suggests that while undoubtedly predatory, Erettopterus was not as active, nor as specialized, as these genera. Erettopterus has been found in North America and in Europe. The Llandovery deposits in Lesmahagow, where the first fossils of E. bilobus were found, preserve fossils of a large amount of other eurypterids, including Nanahughmilleria lanceolata, Hardieopterus lanarkensis, Eusarcana obesus, Parastylonurus sigmoidalis, Carcinosoma scorpionis and Slimonia acuminata.
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Supplementary information The telson (the most posterior segment of the body), which was lanceolate and styliform, is distinctly a Eurypterus-like feature. The marginal compound eyes, the relatively large chelae and the cordate (heart-shaped) metastoma (a large plate that is part of the abdomen) show a great resemblance to Pterygotus. The carapace was parabolic or subquadrate with oval marginal eyes, the chelicerae were able to extend beyond the carapace margin and the appendages II–V were spiniferous. The genus is in various ways similar to the more derived eurypterids of its superfamily, the Pterygotioidea, however, it lacked the expanded and flattened telson that the pterygotids and Slimonia had.
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Thus why the Romans put so much trust in the "balanced sign". Going back to ancient Greek times, Libra the constellation between Virgo and Scorpio used to be ruled over by the constellation of Scorpio. They called the area the Latin word "chelae", which translated to "the claws" which can help identify the individual stars that make up the full constellation of Libra, since it was so closely identified with the Scorpion constellation in the sky. According to the tropical system of astrology, the Sun enters the sign of Libra when it reaches the northern autumnal equinox and the southern vernal equinox, which occurs around September 22.
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Jasus edwardsii Although they superficially resemble true lobsters in terms of overall shape and having a hard carapace and exoskeleton, the two groups are not closely related. Spiny lobsters can be easily distinguished from true lobsters by their very long, thick, spiny antennae, by the lack of chelae (claws) on the first four pairs of walking legs, although the females of most species have a small claw on the fifth pair, and by a particularly specialized larval phase called phyllosoma. True lobsters have much smaller antennae and claws on the first three pairs of legs, with the first being particularly enlarged. Spiny lobsters typically have a slightly compressed carapace, lacking any lateral ridges.
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This estimate exceeds the maximum body size of all other known giant arthropods by almost half a metre even if the extended chelicerae are not included. Jaekelopterus is similar to other pterygotid eurypterids in its overall morphology, distinguished by its triangular telson (the hindmost segment of its body) and inclined principal denticles on its cheliceral rami (the moving part of the claws). The pterygotids, a group of highly derived ("advanced") eurypterids, differ from other groups in several features, especially in the chelicerae and the telson. The chelicerae of the Pterygotidae are enlarged and robust, clearly adapted for active prey capture, with chelae (pincers) more similar to the claws of some modern crustaceans, with well-developed teeth on the claws, relative to the chelicerae of other eurypterid groups.
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Habitat Requirements of the Endangered California Freshwater Shrimp in Streams on the Point Reyes National Seashore and Golden Gate National Recreational Area, United States Geological Survey Males and juveniles are always translucent or transparent, while coloration of the sometimes translucent females ranges from dark brown to purple, some with a broad tan dorsal band. Females may change rapidly from this very dark cryptic color to nearly transparent with diffuse chromatophores. Moreover, females are typically longer and deeper bodied than males. All members of family Atyidae can be distinguished from other shrimp by their overall length as well as the extent length of their pincer-like claws and manifestation of terminal bristles (setae) at the tips of the first and second chelae.
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All species were not this large though, with some (such as A. floweri) only reaching lengths of 20 centimetres (8 in). Other giant pterygotid eurypterids, such as Jaekelopterus and Pterygotus, were very visually acute (possessed good and sharp eyesight) in a similar way to modern predatory arthropods and possessed robust and crushing chelae. Studies on the compound eyes and chelicerae of Acutiramus has revealed that it would have had a comparably low visual acuity and claws adapted for slicing and shearing, rather than crushing. This suggests that the ecological role of Acutiramus was distinct from that of other pterygotids, it potentially lived a lifestyle of ambush predation or scavenging on soft-bodied animals, feeding during the night or in otherwise low-light conditions.
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Within Hughmilleriidae, both genera possessed a marginal rim much broader anteriorly than posteriorly and appendages spiniferous of Hughmilleria-type, but Hughmilleria had 18-20 gnathobasic (of the gnathobase, a lower appendage used in the alimentation) teeth on appendage VI, unlike Herefordopterus and the pterygotids, who had 12-13. Therefore, Hughmilleria represents the most basal form of Pterygotioidea. According to Clifton J. Sarle, Hughmilleria was very similar to Eurypterus, and could be confused with a species of this genus if it was not for the presence of the marginal position of the eyes and the relatively large chelae. However, by its cordate metastoma, the intramarginal to marginal position of the compound eyes, the slightly longer preoral appendages, less developed swimming legs and the opercular appendage, Hughmilleria was more like Pterygotus.
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Periclimenaeus consists of number of species of small shrimps classified in the subfamily Pontoniinae. They occur mainly in tropical seas, especially in and around coral reefs. Periclimanaeus shrimps live in association with a variety of hosts, mostly sponges and ascidian tunicates, where they normally live in the hosts' internal cavities as pairs formed of a male and a female. Characteristics of the genus include the presence of grossly unequal chelae on the second pair of walking legs, the larger of which has a conspicuous molar process on the seventh and terminal segment of the leg, which sits opposite a depression on the fixed finger, this is used to produce sound, a feature which is convergent with similar structures in the related genus Coralliocaris and in some unrelated genera of snapping shrimps from the family Alpheidae.
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As two large pterygotids are already known from the same locality and same timespan as Necrogammarus, Erettopterus and Pterygotus, it is possible that the Necrogammarus remains, in reality, belong to one of these genera. As both genera are only diagnosed and differentiated from each other by features in body parts absent in the Necrogammarus fossil, such as the chelicerae (frontal appendages) and coxae (leg segments), it is impossible to assign Necrogammarus to either of them for the time being. Pterygotids are differentiated from other eurypterids by their flattened telsons (the most posterior segment of the body) and their modified chelicerae (frontal appendages), ending in well-developed chelae (claws). Regardless of its potential identity as either Pterygotus or Erettopterus, these features are likely to have been present in Necrogammarus as well, as all other members of the family possess them.
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The telson of A. cummingsi is not as obovate (ovate with a narrow end at its base) or elongated as that of A. macrophthalmus (which possesses a telson that is six times as long as it is wide), the telson of A. cummingsi is most often just as long as it is wide. The shape of the metastoma of A. bohemicus has been compared to other species in the genus, especially to that of A. cummingsi, which preserves a metastoma that is almost identical in morphology. A. bohemicus is generally agreed to be the species closest in relation to A. cummingsi, though they are differentiated by characteristics in the dentition of the chelae, many of the teeth being larger in A. bohemicus. There may be additional differences, but the incomplete nature of the A. bohemicus material makes further comparisons impossible.
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Prepared Florida stone crab claws The Florida stone crab is usually fished near jetties, oyster reefs or other rocky areas, just as for blue crabs. The bodies of these crabs are relatively small and so are rarely eaten, but the claws (chelae), which are large and strong enough to break an oyster's shell, are considered a delicacy. Harvesting is accomplished by removing one or both claws from the live animal and returning it to the ocean where it can regrow the lost limb(s). To be kept, claws must be long, measured from the tips of the immovable finger to the first joint. In 1978, and in the Everglades National Park Research Center, wild caught crabs were kept in an aquarium for the specifics of testing mortality rates of declawed crabs. With mortality rates of 47 percent for doubly declawed and 28 percent for single declawed crabs were evident.
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The way in which spider crabs are able to pick up and cover themselves with such organisms is by following a specific routine behavior. Upon picking up the object with the crab’s slender chelipeds, the chelae is used to twist and tear off the organism, such as a worm tube or sponge, from the substrate that it currently resides on. Unlike other species of crab, like the Chilean crab Acanthonyx petiveri, the Japanese spider crab does not specifically look for matching colors to blend into their environment; they simply camouflage in a way that disguises their entire structure. This is most likely because Japanese spider crabs are nocturnally active, so instead of trying to disguise themselves when catching prey, they are actually just trying to avoid predators during the night. Once the material is picked up, it is brought to the crabs’ mouthparts to specifically orient and shape it before it is attached to the exoskeleton.
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Kaldane and rykor as illustrated by J. Allen St. John in first edition of Chessmen of Mars The Kaldanes are a fictitious sapient species existing in the region of Bantoom on the planet Barsoom in the John Carter series of books by Edgar Rice Burroughs. Introduced in the book Chessmen of Mars, the Kaldanes are almost all head, but for six arachnoid legs and a pair of chelae. Their racial goal is to achieve pure intellect against bodily existence: In order to function in the physical realm, the Kaldanes have bred the Rykors: a nonsentient complementary species composed of a body similar to that of a Red Martian but lacking a head; when the Kaldane places itself upon the shoulders of the Rykor, a bundle of tentacles connects with the Rykor's spinal cord, allowing the brain of the Kaldane to control its motor nerves and sensory nerves. Should the Rykor become damaged or die, the Kaldane climbs upon another.
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