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Hypsilophodonts (named after ''Hypsilophodon'', itself derived from the ''Hypsilophus'' ("high-crested") genus of iguana lizard and literally meaning "''Hypsilophus''-tooth") were small ornithopod dinosaurs, regarded as fast, herbivorous bipeds on the order of 1–2 meters long (3.3-6.6 feet). They are known from Asia, Australia, Europe, New Zealand, North America, and South America, from rocks of Middle Jurassic to late Cretaceous age. The group traditionally has included almost all bipedal bird-hipped dinosaurs other than iguanodonts, and some early phylogenetic analyses found it to be a natural group, but more recent studies have found that the group is mostly paraphyletic and the taxa within represent a series leading up to Iguanodontia. Some of these studies have moved some traditional hypsilophodonts out of the Ornithopoda, such as ''Agilisaurus'' and ''Othnielosaurus'' (=''Othnielia'').〔 Thus, the only certain member at this time is ''Hypsilophodon''. ==Relationships== The following cladogram of hypsilophodont relationships depicts the paraphyletic hypotheses; the "natural Hypsilophodontidae" hypothesis has been falling out of favor since the mid-late 1990s. It is after Brown ''et al.'' (2013), the most recent analysis of hypsilophodonts. Ornithischia, Ornithopoda, and Iguanodontia were not designated in their result, and so are left out here. Additional ornithopods beyond ''Tenontosaurus'' are omitted. Dinosaurs traditionally described as hypsilophodonts are found from ''Agilisaurus'' or ''Hexinlusaurus'' to ''Hypsilophodon'' or ''Gasparinisaura''. |label2=Thescelosaurinae |2= }} }} |2= }} }} }} }} }} }} }} }} }} In the most recent review of hypsilophodonts, by Norman ''et al.'' (2004),〔 the following genera were known well enough to include in a phylogenetic analysis: *''Agilisaurus'' *''A. multidens'' (now ''Hexinlusaurus'')〔Barrett, P.M., Butler, R. J., and Knoll, F. 2005. Small-bodied ornithischian dinosaurs from the Middle Jurassic of Sichuan, China. Journal of Vertebrate Paleontology 25:823-834.〕 *''Bugenasaura'' (now regarded as a junior synonym of ''Thescelosaurus'')〔 *''Gasparinisaura'' *''Hypsilophodon'' *''Orodromeus'' *''Othnielia'' (now ''Othnielosaurus'') *''Koreanosaurus'' *''Parksosaurus'' *''Thescelosaurus'' *''Zephyrosaurus'' The following genera were regarded as valid, but were not classified:〔 *''Anabisetia'' *''Atlascopcosaurus'' *''Drinker'' *"Gongbusaurus" ''wucaiwanensis'' (= "Eugongbusaurus") *''Fulgurotherium'' *''Jeholosaurus'' *''Leaellynasaura'' *''Notohypsilophodon'' *''Qantassaurus'' *''Yandusaurus'' *"Proctor Lake hypsilophodont" Several other genera belong here somewhere, but are very poorly known or outright dubious:〔 *''Laosaurus'' *''Nanosaurus'' *''Phyllodon'' *''Siluosaurus'' 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「hypsilophodont」の詳細全文を読む スポンサード リンク
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