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''Huabeisaurus'' (, meaning "North China lizard") was a genus of dinosaur from the Late Cretaceous (Cenomanian to Campanian stages, around 99.7–70.6 million years ago). It was a sauropod which lived in what is present-day northern China. The type species, ''Huabeisaurus allocotus'', was first described by Pang Qiqing and Cheng Zhengwu in 2000. ''Huabeisaurus'' is known from numerous remains found in the 1990s, which include teeth, partial limbs and vertebrae. Due to its relative completeness, ''Huabeisaurus'' represents a significant taxon for understanding sauropod evolution in Asia. ''Huabeisaurus'' comes from Kangdailiang and Houyu, Zhaojiagou Town, Tianzhen County, Shanxi province, China. The holotype was found in the unnamed upper member of the Huiquanpu Formation, which is Late Cretaceous (?Cenomanian–?Campanian) in age based on ostracods, charophytes, and fission-track dating. ''Huabeisaurus'' measures long and high, as estimated by Pang and Cheng in 2000. It would have been a quadrupedal herbivore with a long neck and tail, like most other sauropods. The skeleton has been presumed to have belonged to an almost mature individual, because it lacks sutures on vertebrae, but not on pelvic material. A set of 12 characters were identified by D'Emic ''et al.'' in 2013 that differentiate ''Huabeisaurus'' from other sauropods. An isolated humerus, designated the paratype by Pang and Cheng, comes from a locality over 200 meters away from the type locality of ''Huabeisaurus'', in a fluvially deposited sandy conglomeratic layer in the lower member of the Huiquanpu Formation. This layer is roughly 90 m lower stratigraphically than the type horizon of ''Huabeisaurus'', which comes from the upper member of the Huiquanpu Formation. The humerus thus comes from a stratum representing a different and likely older depositional environment than that of ''Huabeisaurus'', and does not overlap anatomically with the holotypic skeleton, and so cannot currently be referred it. The discoverers erected a new family for the genus, Huabeisauridae, although this family name is not widely used amongst paleontologists. Recently, the family was again proposed, this time by D'Emic ''et al.'' because Euhelopodidae, which ''Huabeisaurus'' has been assigned to most recently, might have to be split into smaller clades throughout Somphospondyla because of all the taxa assigned to it. Pang and Cheng tentatively suggested that "Titanosaurus" ''falloti'' be referred to ''Huabeisaurus''. One problem, however, is that the femora of ''Huabeisaurus'' and "T." ''falloti'' differ in the bevel of the distal end versus the long axis of the bone, so the two cannot represent the same genus. ==Description== The Late Cretaceous titanosauriform sauropod ''Huabeisaurus'' is known from teeth and much of the postcranial skeleton. Its completeness makes it an important taxon for integrating and interpreting anatomical observations from more fragmentary Cretaceous East Asian sauropods and for understanding titanosauriform evolution in general. Measuring in total length, ''Huabeisaurus'' is large when compared to most dinosaurs, but by sauropod standards, it was only midsized. It had a hip height of .〔 Like other sauropods, it would have been a quadrupedal herbivore with a long neck and tail.〔Upchurch, Paul; Barrett, Paul M., and Dodson, Peter. (2004). "Sauropoda". In Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka. (eds.). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 259–322.〕 The skeleton has been presumed to have belonged to an almost mature individual. The absence of sutures between the neural arches and centra of cervical, dorsal, and caudal vertebrae suggests that the specimen was nearing sexual maturity, but the open sutures between the scapula and coracoid, and the ilium and some sacral ribs suggest that it had not reached full maturity.〔 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「Huabeisaurus」の詳細全文を読む スポンサード リンク
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