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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.〕 ==Discoveries and species== ''Brachyceratops montanensis'', the type species, was first discovered in the Two Medicine Formation (Campanian, about 74 million years old) on a Blackfoot Indian Reservation in Teton County in north-central Montana.〔"Brachyceratops." In: Dodson, Peter & Britt, Brooks & Carpenter, Kenneth & Forster, Catherine A. & Gillette, David D. & Norell, Mark A. & Olshevsky, George & Parrish, J. Michael & Weishampel, David B. ''The Age of Dinosaurs''. Publications International, LTD. p. 133. ISBN 0-7853-0443-6.〕 The original find was made in August 1913 by C. W. Gilmore〔 and his assistant J. Floyd Strayer and was named and shortly described by Gilmore one year later. The generic name is derived from Greek βραχύς, ''brachys'', "short", κέρας, ''keras'', "horn" and ὤψ, ''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〕 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.〔 The holotype specimen is USNM 7951, a partial skull. The paratypes are USNM 7952, a snout, USNM 7953, a partial skeleton with skull and USNM 7957, a foot. The material is disarticulated but the preservation is excellent.〔Dodson, P., 1996, ''The Horned Dinosaurs — A natural history'', Princeton University Press, p. 154〕 In 1917 Gilmore published a monography on ''Brachyceratops'' in which a reconstruction of the skeleton as a whole was given.〔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. By 2011 however, several studies had shown that the single specimen which was adult enough to be compared with related species, USNM 14765, represented the juvenile form of the later-named ''Rubeosaurus''. 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「Brachyceratops」の詳細全文を読む スポンサード リンク
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