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''Suchosaurus'' (meaning "crocodile lizard") is as a spinosaurid theropod dinosaur from Cretaceous England, originally believed to be a genus of crocodile. The type material consists of teeth. Two species, ''S. cultridens'' and ''S. girardi'' have been named. About 1820, Gideon Mantell acquired some spinosaurid teeth discovered near Cuckfield in the Wadhurst Clay of East Sussex, part of a lot with the present inventory number BMNH R36536. In 1822, he reported these, after an identification by William Clift, as belonging to crocodiles.〔Mantell, G.A., 1822, ''The fossils of the South Downs or Illustrations of the Geology of Sussex'', London, Rupton Relfe〕 In 1824, the teeth were mentioned and illustrated by Georges Cuvier, representing the first illustration of a spinosaurid fossil.〔Cuvier, G., 1824, ''Recherches sur les ossemens fossiles, deuxième édition''. Dufour & d’Ocagne, Paris. 547 pp〕 In 1827 Mantell described additional teeth, pointing out the similarities to the crocodylian ''Teleosaurus'' and ''Gavialis''.〔Mantell, G.A., 1827, ''Illustrations of the geology of Sussex'', London, Lupton Relfe. 92 pp〕 One of these teeth is the present specimen BMNH R4415, others are part of BMNH R36536. In 1841, Richard Owen named, based on BMNH R36536 as a syntype series, a subgenus ''Crocodylus (Suchosaurus)'' with as type species ''Crocodylus (Suchosaurus) cultridens''.〔Owen, R. (1840–1845). ''Odontography''. London: Hippolyte Baillière, 655 pp, 1–32〕 The subgeneric name was derived from Greek σοῦχος, ''souchos'', the name of the Egyptian crocodile god Sobek. This reflected the presumed taxonomic affinities; at the time Owen was not aware of the crocodile-like snouts of spinosaurids. The specific name is derived from Latin ''culter'', "dagger", and ''dens'', "tooth", in reference to the elongated form of the teeth. In 1842, Owen again mentioned the taxon as a subgenus,〔Owen, R., 1842, ''Report on British fossil reptiles. Part II''. Reports of the meetings of the British Association for the Advancement of Science. 11, pp 61-204〕 subsequently he and other workers would use it as a full genus ''Suchosaurus''. In 1842 and 1878 Owen referred some vertebrae to ''Suchosaurus'',〔Owen, R., 1878, ''Monograph on the fossil Reptilia of the Wealden and Purbeck Formations. Supplement VIII, (Goniopholis, Petrosuchus, and Suchosaurus)''. Palaeontolographical Society Monographs, 32, pp 1-15〕 but these likely belong to Ornithischia instead.〔 In 1884, Owen indicated a tooth as "Suchosaurus leavidens" in a caption,〔 *Owen, R., 1884, ''A History of British Fossil Reptiles, Volume II''. Cassell, London. 224 pp〕 this is usually seen as a ''lapsus calami'' because this species is not further mentioned. In 1897, Henri-Émile Sauvage named a second species: ''Suchosaurus girardi'', based on two jaw fragments (specimen MG324) and a tooth, found in Portugal by Paul Choffat. The specific name honours French geologist Albert Girard.〔Sauvage, H. E. (1897–1898). ''Vertébrés fossiles du Portugal. Contribution à l’étude des poissons et des reptiles du Jurassique et du Crétacique.'' Lisbonne: Direction des Travaux géologiques du Portugal, 46p〕 The tooth was considered lost but was rediscovered and in 2013 reported as specimen MNHN/UL.I.F2.176.1, part of remains recovered after a fire in 1978.〔Malafaia, E.; Ortega, F.; Escaso, F.; Mocho, P., 2013, "Rediscovery of a lost portion of the holotype of ''Suchosaurus girardi'' (Sauvage, 1897-98), now related to the spinosaurid theropod ''Baryonyx''", In: Torcida Fernández-Baldor, F.; Huerta, P. (Eds.). ''Abstract book of the VI International Symposium about Dinosaurs Palaeontology and their Environment'' pp 82-84〕 During the nineteenth and most of the twentieth century, ''Suchosaurus'' was usually considered to have been some obscure crocodilian, perhaps belonging to the Pholidosauridae.〔Buffetaut, E., 2010, "Spinosaurs before Stromer: Early finds of spinosaurid dinosaurs and their interpretations", ''Geological Society, London, Special Publications. 343'', pp 175-188〕 Single comparable teeth discovered in England were referred to the genus.〔Lydekker, R., 1888, ''Catalogue of the Fossil Reptilia and Amphibia in the British Museum (Natural History), Cromwell Road, S.W., Part 1. Containing the Orders Ornithosauria, Crocodilia, Dinosauria, Squamata, Rhynchocephalia, and Proterosauria''. British Museum of Natural History, London. 309 pp〕 However, when publishing a redescription of ''Baryonyx'' in 1998, Angela Milner realised that the teeth of that spinosaurid dinosaur were extremely similar to those of ''Suchosaurus''. In 2003, she suggested both genera represented one and the same animal.〔Milner, A., 2003, "Fish-eating theropods: A short review of the systematics, biology and palaeobiogeography of spinosaurs". In: Huerta Hurtado and Torcida Fernandez-Baldor (eds.). ''Actas de las II Jornadas Internacionales sobre Paleontologýa de Dinosaurios y su Entorno (2001)''. pp 129-138〕 An identity would imply the name ''Suchosaurus'' has priority. However, the ''Suchosaurus'' teeth are also indistinguishable from those of ''Cristatusaurus'' and ''Suchomimus'', making it an indeterminate baryonychine. The ''S. girardi'' material was reclassified by Eric Buffetaut as cf. ''Baryonyx walkeri'' in 2007.〔Buffetaut, E. (2007). "The spinosaurid dinosaur ''Baryonyx'' (Saurischia, Theropoda) in the Early Cretaceous of Portugal." ''Geological Magazine'', 144(6): 1021-1025. 〕 Of the remaining species, ''S. cultridens'', he affirmed that the holotype teeth strongly resembled those of ''Baryonyx walkeri''. While there are some differences between the teeth, these may or may not represent individual variation among specimens, and he concluded that ''Suchosaurus'' may be a senior synonym of ''Baryonyx''.〔 ''Suchosaurus'' was considered a ''nomen dubium'' by Octávio Mateus ''et al.'' (2011).〔Mateus, O., Araújo, R., Natário, C. & Castanhinha, R. 2011. ''Zootaxa'' 2827: 54–68.〕 ==References== 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「Suchosaurus」の詳細全文を読む スポンサード リンク
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