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''Nothronychus'' is a genus of theropod dinosaur classified in the group Therizinosauria, from the Cretaceous of North America. The type species of this dinosaur, ''Nothronychus mckinleyi'', was described by James Kirkland and Douglas G. Wolfe in 2001. It was recovered near New Mexico's border with Arizona, in an area known as the Zuni Basin, from rocks assigned to the Moreno Hill Formation, dating to the late Cretaceous period (mid-Turonian stage), around 91 million years ago. A second specimen, described in 2009 as a second species, ''Nothronychus graffami'', was found in the Tropic Shale of Utah, dating to the early Turonian, between one million and a half million years older than ''N. mckinleyi''. The name ''Nothronychus'', is derived from Greek, meaning "slothful claw."〔 ''Nothronychus'' was a herbivorous theropod with a beak, a bird-like hip (resembling that of the non-related ornithischians) and four-toed feet, with all four toes facing forward. ==Description== ''Nothronychus'' was a member of the Coelurosauria, the theropod group of carnivorous dinosaurs that includes carnivores such as ''Tyrannosaurus''. However, more specifically, ''Nothronychus'' was a part of the sub-group Maniraptora, theropods which evolved into omnivores and, in the case of ''Nothronychus'' and its family, plant-eaters.〔 It was bipedal and walked more upright than its carnivore ancestors. ''N. graffami'' weighed about a tonne, were 4.5–6 m (15–20 ft) long and stood 3-3.6 m (10–12 ft) tall, while ''N. mckinleyi'' was only slightly smaller.〔 A reconstruction of 40 to 50 percent of its skeleton, from the two separate species, allowed scientists to describe these dinosaurs as having leaf-shaped teeth with circular roots, long necks, long arms with dexterous hands and, measured over the curve, up to thirty centimeter (12 in) long curved claws on their fingers, large "pot-bellied" abdomens, stout hind legs, and relatively short tails. ''N. mckinleyi'' was different from ''N. graffami'' in being less robust as well as details of the tail vertebrae, and a more bent lower arm bone (ulna).〔 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「Nothronychus」の詳細全文を読む スポンサード リンク
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