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:''Not to be confused with another sauropod dinosaur, Cetiosaurus''. ''Cetiosauriscus'' ( meaning "whale lizard like" i.e. "''Cetiosaurus''-like") is an extinct genus of sauropod dinosaur. It lived in the Callovian (Middle to Late Jurassic Period) of England (about 165 to 161 million years ago ()). ''Cetiosauriscus'' was a quadrupedal, herbivorous, saurischian, and was possibly the earliest diplodocid. It was named by Friedrich von Huene in 1927, for the species ''Cetiosaurus leedsi''. Before 1993 it was shown that ''C. leedsi'' was not a ''Cetiosauriscus'' species, so that year Alan J. Charig sent a petition to the ICZN to designate ''C. stewarti'' as the type species. The remains include a series of vertebra, a hind leg, a partial sacrum, and a front leg. A potential additional specimen includes a diplodocid whiplash tail. ''Cetiosauriscus'' has, over time, been classified in Cetiosauridae, Diplodocidae, and Mamenchisauridae. It lived alongside ''Sarcolestes'', ''Callovosaurus'', and ''Lexovisaurus''. ==Description== ''Cetiosauriscus'' was a relatively small quadrupedal, herbivorous sauropod. It is estimated by Gregory S. Paul that ''Cetiosauriscus'' stood high and was in length, weighing about .〔 Another estimate, by Thomas R. Holtz Jr., had ''Cetiosauriscus'' standing up to long and weighing roughly .〔 The only overlapping material between BMNH R3078 and the holotype of ''Cetiosauriscus leedsi'' is an ilium. However, in both specimens the ilium was preserved in insufficient ways. Since the only overlapping material was impossible to compare, Charig found that BMNH R3078 was of a different species and he named it ''Cetiosauriscus stewarti''.〔〔 Metacarpal 1 is short and massive, with the prominent process on the lower part of the posterior margin of the lateral face, a characteristic of the diplodocoids ''Diplodocus'', ''Apatosaurus'', ''Cetiosauriscus'' and ''Dicraeosaurus''.〔 Huene felt the vertebrae of BMNH R3078 had proportions different enough from ''Cetiosaurus'' to warrant its own genus. Also, the fusion of centra with minimal osseous proliferation is manifest in the caudal vertebrae of ''Cetiosauriscus''.〔 The ''Cetiosaurus'' specimen OUMNH J13695 has a low horizontal ridge on each of its lateral surfaces, creating a slightly subhexagonal tranverse cross-section, and is also seen on ''Cetiosauriscus'', as well as the anterior caudals of ''Haplocanthosaurus'', and caudals 15 to 30 of ''Omeisaurus''. Also, the area around the periphery of each articular face is flattened, creating a 'bevelled' appearance, and also occurs in ''Cetiosaurus'' and ''Haplocanthosaurus''.〔 A whiplash tail was apparently found in the same deposits but it is not certain it belongs to the same individual. Since there is no overlapping material, this assignment to ''Cetiosauriscus'' should be treated with caution.〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cetiosauriscus」の詳細全文を読む スポンサード リンク
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