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''Eubrontes'' (Hitchcock, 1845) is the name of fossilised dinosaur footprints dating from the Late Triassic and Early Jurassic. They have been identified from France, Poland, Slovakia, Italy, Spain, Sweden, Australia (Queensland) and the USA. It is a junior synonym of ''Grallator''. ''Eubrontes'' is the name of the footprints, identified by their shape, and not of the genus or genera that made them, which is as yet unknown. They are most famous for their discovery in the Connecticut River Valley of Massachusetts in the early 19th century. They, among other footprints, were the first known dinosaur remains to be discovered in North America, though they were initially thought to have been made by large birds. ==Discovery and Identity== The footprints were first described by Edward Hitchcock, a professor of Amherst College, who thought they were made by a large bird. He originally assigned them to ichnotaxon ''Ornithichnites'' in 1836, then ''Ornithoidichnites'' in 1841, before coining ''Eubrontes'' in 1845. The name means "true thunder," probably referring to the supposed weight of the animal impacting on the ground. in 1858 Hitchcock still described the tracks as those of "a thick-toed bird," since there was no evidence of tail drag marks. But by the time that Richard Swann Lull began working on the tracks in 1904, they were thought to belong to a dinosaur. Lull originally thought they were from a herbivore, but by 1953 he concluded they were from a carnivorous theropod. Many later authors have agreed with this interpretation, but some have suggested that they are from a prosauropod. Regardless, they are almost certainly saurischian.〔Robert E. Weems. 2003. "''Plateosaurus'' foot structure suggests a single trackmaker for ''Eubrontes'' and ''Gigandipus'' footprints." In P. M. LeTourneau & P. E. Olsen (eds.). ''The Great Rift Valleys of Pangea in Eastern North America, Volume 2: Sedimentology, Stratigraphy, and Paleontology.'' New York: Columbia University Press, pp. 294–295.〕 A typical ''Eubrontes'' print is from 25–50 cm long, with three toes that terminate in sharp claws. It belongs to a biped that must have been over one metre high at the hip and from 5–6 metres long. In the 1960s Edwin Colbert and others supposed that a large heavy carnivore like ''Teratosaurus'' (then considered to be a dinosaur) made the track, but a possible candidate is ''Dilophosaurus'', a large theropod related to ''Coelophysis'', or a close relative such as ''Podokesaurus''. However no ''Dilophosaurus'' fossil material is associated with ''Eubrontes'' tracks. The tracks may also be from a plateosaurid. Another major find occurred at Rocky Hill, Connecticut in 1966. Nearly 600 prints are preserved there in an area now designated Dinosaur State Park. 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「Eubrontes」の詳細全文を読む スポンサード リンク
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