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''Paranthodon'' (〔) is a genus of extinct stegosaurian dinosaur that lived in South Africa during the Early Cretaceous, approximately 145.5–136.4 million years ago. Discovered in 1845, it was one of the first stegosaurians found. Its only remains, a partial skull and isolated teeth, were found in the Kirkwood Formation. Although Owen initially identified the fragments as those of the pareiasaur ''Anthodon'', after years of storage in the British Museum of Natural History, Broom identified the partial skull as belonging to a different genus, and named the specimen ''Palaeoscincus africanus''. Several years later, Nopcsa, unaware of Broom's new name, similarly concluded that it represented a new taxon, and named the binomial ''Paranthodon owenii''. However, since the Nopcsa's species name was assigned after Broom's, and Broom did not assign a new genus, both names are now synonyms under the current naming, ''Paranthodon africanus''. The genus name was chosen from the Ancient Greek ''para'', "near" and ''Anthodon'', for the originally proposed similarity of the specimens. In identifying the remains as those of ''Palaeoscincus'', Broom basically classified ''Paranthodon'' as an ankylosaurian, a statement backed by the research of Coombs. Nopcsa however, identified the genus as a stegosaurid, which most modern studies agree with. In 1981, the genus was reviewed, and found to be a valid genus of stegosaurid. ''Paranthodon'' is one of a few genera found in the Kirkwood Formation; other such taxa include theropods, like ''Nqwebasaurus''; ornithopods; and sauropods, like ''Algoasaurus''. ==Discovery and naming== In 1845, amateur geologists William Guybon Atherstone and Andrew Geddes Bain discovered several fossils near Dassieklip, Cape Province, in the Bushmans River Valley.〔 This was the first dinosaur find in all of the Southern Hemisphere and Africa. In 1849 and 1853, Bain sent some of the fossils to the British paleontologist Richard Owen for identification. Among them was an upper jaw Bain referred to as the "Cape ''Iguanodon''"; as such the site was named "Iguanodonhoek". Atherstone published about the find in 1857, but lamented in 1871 that it had thus far received no attention in London. Only in 1876 did Owen name a series of specimens from the collection as ''Anthodon serrarius''.〔 ''Anthodon'' means "flower tooth". The partial holotype skull BMNH 47337, the left jaw BMNH 47338, the matrix BMNH 47338 including bone fragments and impressions of the anterior skull, and the vertebrae BMNH 47337a were all assigned to ''Anthodon.''〔 In 1882, Othniel Charles Marsh assigned ''Anthodon'' to Stegosauridae based on BMNH 47338, and in 1890, Richard Lydekker found that although ''Anthodon'' was a pareiasaur, its teeth were similar to those of Stegosauridae.〔 In 1909, the South-African paleontologist Robert Broom visited the collection of the British Museum of Natural History. He concluded that Owen had mixed the partial distorted skull, teeth, and a mandible of a pareiasaur and a partial upper jaw of a dinosaur BMNH 47338, which were actually from two different species.〔 Broom kept the name ''Anthodon'' for the pareiasaur, but identified the other fossil as a member of the genus ''Palaeoscincus'', naming the new species ''Paleoscincus africanus'' in 1912. He found that the anatomy of the teeth were quite different, even thought they resembled each other, as well as those of ''Stegosaurus''. In 1929, Baron Franz Nopcsa, unaware of Broom's previous publication, provided a new name for Broom's ''P. africanus'', as D.M.S. Watson believed that the jaw should be differentiated from ''Anthodon''. Nopcsa named the species ''Paranthodon Owenii'', with the genus name derived from the Latin ''para'', meaning "similar", "near", or "beside", and ''Anthodon'', and specific name honoring Owen.〔 Due to present conventions, the specific name was later emended to ''owenii''.〔 In 1978, Walter Coombs incorporated both names into the current nomenclature, ''Paranthodon africanus'', as ''Paranthodon'' was the first new genus for the fossils and ''africanus'' was the first named species. This makes ''Palaeoscincus africanus'' and ''Paranthodon owenii'' junior synonyms of ''Paranthodon africanus''.〔 The holotype of ''Paranthodon'', BMNH 47338, was found in a layer of the Kirkwood Formation dated between the Berriasian and early Valanginian ages. It consists of the back of the snout, containing the maxilla with teeth, the posterior caudodorsal ramus of the premaxilla, part of the nasals, and some isolated teeth probably from the lower jaw. One additional specimen can be assigned to it based on the dentition, BMNH 47992, including only isolated teeth sharing the same morphology as those from the holotype. However, the teeth do not bear any autapomorphies of ''Paranthodon'', and were referred to an indeterminate stegosaurid in 2008. 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「Paranthodon」の詳細全文を読む スポンサード リンク
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