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''Tornieria'' ("for Tornier") is a genus of diplodocid sauropod dinosaur from Late Jurassic of Tanzania. It has a convoluted taxonomic history. ==Discovery and naming== In 1907, German paleontologist Eberhard Fraas who was working the Tendaguru Beds in German East Africa (presently Tanzania), discovered two sauropod specimens at a single site ("Quarry A"). The two individuals, designated "Skeleton A" and "Skeleton B", each represented a different sauropod species. In 1908 he named these respectively ''Gigantosaurus africanus'' ("African giant lizard") and ''G. robustus'' ("Robust giant lizard").〔E. Fraas, 1908, "Dinosaurierfunde in Ostafrika", ''Jahreshefte des Vereins für Vaterländische Naturkunde in Württemberg'' 64: 84-86〕 A third, unrelated African species, "Gigantosaurus" ''dixeyi'', was named by Haughton in 1928, and has since been reassigned to ''Malawisaurus''. However, the name ''Gigantosaurus'' had already been used for the European sauropod ''Gigantosaurus megalonyx'' Seeley, 1869. Fraas, not intending to place his species in the same genus as this English form, had believed that the name was available, since at the time the latter species was considered to be a junior synonym of ''Ornithopsis'' and Seeley in his opinion had not provided a sufficient description anyway. Another German paleontologist, Richard Sternfeld, renamed the Tanzanian sauropod ''Tornieria'' in 1911, making the two species ''Tornieria africana'' and ''T. robusta''. The generic name honours the German herpetologist Gustav Tornier.〔Sternfeld, R., 1911, "Zur Nomenklatur der Gattung ''Gigantosaurus'' Fraas", ''Sitzungsberichte der Gesellschaft naturforschender Freunde zu Berlin'' 1911: 398〕 A re-evaluation of ''Tornieria'' in 1922 by Werner Janensch concluded that one species, ''T. africana'', was actually an African species of the North American sauropod genus ''Barosaurus'': ''Barosaurus africanus''.〔Janensch, W., 1922, "Das Handskelett von ''Gigantosaurus robustus'' und ''Brachiosaurus brancai'' aus den Tendaguru-Schichten Deutsch- Ostafrikas", ''Centralblatt für Mineralogie, Geologie und Paläontologie'' 1922: 464–480〕 The other African species, ''T. robusta'', later turned out to belong to a titanosaur. The titanosaur species for a time was called ''Tornieria'', but this was incorrect as ''T. africana'' had been the type species. It needed a generic name of its own and this was provided in 1991 when Rupert Wild renamed it ''Janenschia''. If ''Tornieria'' were the same genus as ''Barosaurus'', then the name ''Tornieria'' would be abandoned as a junior subjective synonym. However, later researchers proposed generic distinction between the American and the African form. In the early 21st century this usage became prevalent and in 2006 Kristian Remes in a review concluded that ''Tornieria'' was indeed distinct and a valid genus.〔Remes, K., 2006, "Revision of the Tendaguru sauropod ''Tornieria africana'' (Fraas) and its relevance for sauropod paleobiogeography", ''Journal of Vertebrate Paleontology'' 26(3): 651–669〕 A complication is formed by the fact that Janensch in 1961 recognised a variety of ''B. africanus'': ''B. africanus'' var. ''gracilis'', a morph distinguished by more gracile hind limbs.〔Janensch, W., 1961, "Die Gliedmaßen und Gliedmaßengürtel der Sauropoden der Tendaguru-Schichten", ''Palaeontographica'' Supplement 7(3): 177–235〕 In 1980 John McIntosh promoted this to a full species: ''Barosaurus gracilis''〔D. Russell, P. Beland, and J. McIntosh, 1980, "Paleoecology of the dinosaurs of Tendaguru (Tanzania)", Memoires de la Societé Geologique de France, N.S. 139: 169-175〕 which then would become a ''Tornieria gracilis'' under the present usage, a combination already published by George Olshevsky in 1992.〔G. Olshevsky, 1992, ''A revision of the parainfraclass Archosauria Cope, 1869, excluding the advanced Crocodylia''. Mesozoic Meanderings 2, pp. 1-268〕 However, Remes in 2006 concluded that ''B. gracilis'' had been a ''nomen nudum'', neither holotype nor diagnosis having been provided in 1980.〔 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「Tornieria」の詳細全文を読む スポンサード リンク
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