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''Monolophosaurus'' ( ; meaning "single-crested lizard") is a genus of tetanuran theropod dinosaur from the Middle Jurassic Shishugou Formation in what is now Xinjiang, China. It was named for the single crest on top of its skull. ==Discovery and naming== A nearly complete skeleton of a theropod new to science was discovered by a Canadian-Chinese expedition in 1981. The fossil was unearthed until 1984. In 1987, before description in the scientific literature, it was referred to in the press as ''Jiangjunmiaosaurus'', an invalid ''nomen nudum''.〔 In 1992 it was mentioned by Dong Zhiming as ''Monolophosaurus jiangjunmiaoi'',〔 Dong, Z., 1992, ''Dinosaurian Faunas of China'', Ocean Press/Springer-Verlag, Beijing/Berlin. 188 pp〕 and in 1993 by Wayne Grady as ''Monolophosaurus dongi''.〔Grady, W., 1993, ''The Dinosaur Project — The Story of the Greatest Dinosaur Expedition Ever Mounted'', Edmonton: Ex Terra Foundation. Toronto: Macfarlane Walter & Ross. 61 pp〕 These latter names also lacked a description and therefore were ''nomina nuda'' as well. In 1993/1994, Zhao Xijin and Philip John Currie named and described the type species ''Monolophosaurus jiangi''. The generic name is derived from Greek μόνος, ''monos'', "single", and λόφος or λόφη, ''lophos/lophè'', "crest", in reference to the single crest on the snout. The specific name refers to Jiangjunmiao, an abandoned desert inn, near which the fossil was found.〔 Jiangjunmiao means "the temple (''miao'') of the general (''jiangjun'')"; local legend has it that a general was buried here. The holotype, IVPP 84019, was discovered in the Junggar Basin, in layers of the Wucaiwan Formation dating from the Bathonian-Callovian. It consists of a rather complete skeleton including the skull, lower jaws, vertebral column and pelvis. The rear of the tail, the shoulder girdle and the limbs are lacking. It represents an adult or subadult individual.〔 The type specimen was restored with plaster to be used in a travelling exhibit. Its left side was encased in foam which has hindered subsequent study. A reconstruction was made of the missing elements to create casts of complete skeletal mounts. In 2010, two studies by Stephen Brusatte e.a. redescribed the holotype, at the time still the only specimen known, in detail.〔〔 In 2006, Thomas Carr suggested that ''Guanlong'', another theropod with a large, thin, and fenestrated midline crest and from the same formation, was in fact a subadult individual of ''Monolophosaurus''. Usually ''Guanlong'' had been considered a proceratosaurid tyrannosauroid, but Carr had performed an analysis in which both specimens clustered and were allosauroids. More conservatively, in 2010 Gregory S. Paul renamed ''Guanlong'' into a ''Monolophosaurus'' species, ''Monolophosaurus wucaii'',〔Paul, G.S., 2010, ''The Princeton Field Guide to Dinosaurs'', Princeton University Press p. 93-94〕 presuming the taxa might be sister species. In 2010, Brusatte e.a. rejected the identity, pointing out that the ''Guanlong'' holotype was actually a fully adult individual.〔 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「Monolophosaurus」の詳細全文を読む スポンサード リンク
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