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''Becklespinax'' is a genus of large predatory theropod dinosaur from the Early Cretaceous of England. ==Discovery== Probably during the early 1850s, fossil collector Samuel Husband Beckles discovered some nodules with dinosaur bones in a quarry near Battle, East Sussex. These he sent to palaeontologist Richard Owen, who reported them in 1856.〔Owen, R., 1856, ''Monograph on the fossil Reptilia of the Wealden Formation. Part IV''. Palaeontographical Society Monographs 10, 26 pp〕 Owen had a lithography made by Joseph Dinkel of the main specimen, a series of three back vertebrae with very tall spines, whose image was also shown in an 1884 edition of an 1855 volume of his standard work on British fossil reptiles,〔Owen, R., 1855, ''Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Part II. Dinosauria (Iguanodon). (Wealden)''. Palaeontographical Society Monographs 8. 54 pp〕 leading to the misunderstanding the fossils had been recovered close to 1884. Owen, who referred the specimens to ''Megalosaurus bucklandii'', thought the vertebrae were part of the shoulder region and it has been assumed that he must have already known of the find in 1853 as he directed Benjamin Waterhouse Hawkins to put a hump on the back of the life-sized ''Megalosaurus'' sculpture in Crystal Palace Park, which again inspired other restorations from the 19th century.〔Naish, D. 2010. "Pneumaticity, the early years: Wealden Supergroup dinosaurs and the hypothesis of saurischian pneumaticity". In: Moody, R. T. J., Buffetaut, E., Naish, D. & Martill, D. M. (eds) ''Dinosaurs and Other Extinct Saurians: A Historical Perspective''. Geological Society, London, Special Publications 343, pp. 229-236〕 In 1888 Richard Lydekker associated the vertebrae with material referred to ''Megalosaurus dunkeri'', a Cretaceous form based on a tooth found in Germany.〔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〕 In 1923 Friedrich von Huene created a separate genus for ''Megalosaurus dunkeri''. He referred the three vertebrae to this genus and based its name, ''Altispinax'' (meaning "with high spines") on their appearance. ''Megalosaurus dunkeri'' hereby received the new combination name ''Altispinax dunkeri'', a combination actually used for the first time in 1939 by Oskar Kuhn.〔Kuhn, O., 1939, ''Saurischia — Fossilium catalogus I, Animalia, Pars 87''. 's-Gravenhage, W. Junk, 1939, 124 pp〕 Later it was understood that ''Altispinax'' was a ''nomen dubium'' because the original tooth was undiagnostic. No relationship could be proven with the vertebrae. These were therefore in 1988 by Gregory Paul named as a new species of ''Acrocanthosaurus'', ''Acrocanthosaurus? altispinax''. The specific name was deliberately made identical to the old generic name, to emphasize that both referred to the vertebrae.〔Paul, G.S., 1988, ''Predatory Dinosaurs of the World''. Simon & Schuster, New York 464 pp〕 As indicated by the question mark, Paul himself was uncertain about this assignment. In 1991 for this reason a new genus, ''Becklespinax'', was named by George Olshevsky, in honour of the original discoverer, Beckles. The new combination name of the type species ''Acrocanthosaurus? altispinax'' thus became ''Becklespinax altispinax''.〔Olshevsky, G., 1991, ''A revision of the parainfraclass Archosauria Cope, 1869, excluding the advanced Crocodylia. Mesozoic Meanderings 2'', 196 pp〕 The species names ''Altispinax altispinax''〔Rauhut, O.W.M., 2000, ''The interrelationships and evolution of basal theropods (Dinosauria, Saurischia)''. Ph.D. dissertation, University of Bristol, 440 pp〕〔Rauhut, O.W.M., 2003, ''The Interrelationships and Evolution of Basal Theropod Dinosaurs. Special Papers in Palaeontology no. 69'', London, The Palaeontological Association 213 pp〕 and ''Altispinax lydekkerhueneorum''〔Pickering, S., 1995, ''Jurassic Park: Unauthorized Jewish Fractals in Philopatry, A Fractal Scaling in Dinosaurology Project'', 2nd revised printing, Capitola, California, 478 pp〕 are its junior objective synonyms, i.e. they refer to the same material but the name ''Becklespinax altispinax'' has priority. The holotype of ''Becklespinax'', BMNH R1828, was probably found in a layer of the Hastings Bed Group dating from the late Valanginian. It consists of a series of three posterior dorsal vertebrae. Owen also reported the presence in the nodules of two right ribs and two additional series of two dorsal vertebral centra each.〔 Olshevsky thought the holotype represented the eighth, ninth, and tenth dorsal vertebra; later researchers, however, have assumed them to be the tenth, eleventh and twelfth.〔 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「Becklespinax」の詳細全文を読む スポンサード リンク
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