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''Szechuanosaurus'' ("Szechuan lizard") is a dubious〔Chure, D.J. (2000) ''A new species of'' Allosaurus ''from the Morrison Formation of Dinosaur National Monument (UT–CO) and a revision of the theropod family Allosauridae''. Unpublished Ph.D. dissertation, Columbia University, New York〕 genus of carnivorous theropod dinosaur from the Late Jurassic. Fossils referred to the genus have been found in Asia in the Oxfordian and early Kimmeridgian (Peng ''et al''., 2005).〔Peng, G.Z., Ye, Y., Gao, Y.H., Shu, C.K., Jiang, S. (2005): ''Jurassic dinosaur faunas in Zigong''. Sichuan People’s Publishing House, 236 pp〕 Its type species is largely based on several undiagnostic teeth from the Shangshaximiao Formation. ==Discovery and species== Three species have been assigned to this genus over the years. The type species is ''Szechuanosaurus campi'', named by Yang Zhongjian ("Chung Chien Young") in 1942 for four isolated tooth specimens: IVPP V235, two partial teeth; IVPP V236, a partial tooth; IVPP V238, several tooth fragments; and IVPP V239, a single tooth. The teeth form a syntype series and were not found together. Also a very fragmentary skeleton, specimen UCMP 32102, was by Yang listed as part of the type material.〔Young, C.C., 1942, "Fossil vertebrates from Kuangyuan, N. Szechuan, China", ''Bulletin of the Geological Society of China'', 22: 293-309〕 Some of the teeth indicate a large body-size. These fossils, although possibly sinraptorid, are now considered to be non-diagnostic, making ''S. campi'' a ''nomen dubium''.〔Brusatte, S. L., Benson, R. B. J., and Xu, X. 2010. "The evolution of large-bodied theropod dinosaurs during the Mesozoic in Asia". ''Journal of Iberian Geology'', 36: 275-296〕 The generic name refers to Szechuan. The specific name honours the American paleontologist Charles Lewis Camp who had discovered UCMP 32102.〔Camp, C.L., 1935, "Dinosaur remains from the Province of Szechuan", ''Bulletin of the Department of Geology of the Univiversity of California'' 23: 467-471〕 ''S. campi'' is also sometimes reported to include ''Chienkosaurus ceratosauroides'', although some researchers still believe that the latter may yet prove to be a distinct species. A partial skeleton, CV 00214, was initially listed by Dong ''et al.'' (1978) in a faunal list as a new species of ''Szechuanosaurus'', ''Szechuanosaurus yandonensis''.〔Dong, Z., Chang, Li & Zhou, 1978, "Note on a new carnosaur ''Yanchuangosaurus shangyuanensis'' gen. et sp. nov.) from the Jurassic of Yangchuan District, Szechuan Province", ''Kexue Tongabao'' 5: 302-304〕 At first, there was no description or illustration of it, making ''S. yandonensi'' at the time a ''nomen nudum''. Later, Dong Zhiming ''et alii'' (1983) described it, and assigned it to ''Szechuanosaurus campi''〔Dong, Z-M., Zhou, S., Zhang, Y. (1983): (dinosaurian remains of Sichuan Basin, China ). Palaeontologica Sinica (new series C), 23: 1–145 (Chinese with English summary ).〕 The affinities of this skeleton are uncertain, and it has only been briefly described. Holtz ''et al''. (2004) included it in their phylogenetic analysis and found it to be the most basal tetanuran.〔Holtz, T.R., Molnar, R.E., Currie P.J. (2004): Basal Tetanurae. In: D.B. Weishampel, P. Dodson, P., H. Osmólska (ed.), ''The Dinosauria'', 2nd edn. University of California Press, Berkeley, 71-110〕 This individual was a medium-sized theropod, with an ischium (a pelvic bone) of ; for comparison, an ischium of ''Piatnitzkysaurus'' estimated to weigh is long.〔 In 2000, Daniel Chure referred the specimen to "Szechuanoraptor dongi", itself an invalid ''nomen ex dissertatione''.〔 Carrano, Benson & Sampson (2012) synonymized it with ''Yangchuanosaurus shangyouensis'' from the same formation.〔 The third species is ''Szechuanosaurus zigongensis'', named by Gao Yuhui in 1993 for an almost complete skeleton, specimen ZDM 9011.〔Gao, Y., 1993, "A new species of ''Szechuanosaurus'' from the Middle Jurassic of Dashanpu, Zigong, Sichuan", ''Vertebrata PalAsiatica'' 31(4): 308-314〕 It is an older species, from the Middle Jurassic, appearing to be distinct from the type species and therefore requires its own genus name.〔 It was reassigned to ''Yangchuanosaurus'', as a ''Yangchuanosaurus zigongensis'', by Matthew Carrano, Roger Benson & Scott Sampson in 2012. 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「Szechuanosaurus」の詳細全文を読む スポンサード リンク
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