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''Crichtonpelta'' is a genus of extinct herbivorous ankylosaurid dinosaur from the Cretaceous of China. In 2007, Lü Junchang, Ji Qiang, Gao Yubo and Li Zhixin named and described a second species of ''Crichtonsaurus'': ''Crichtonsaurus benxiensis''. The specific name refers to the Benxi Geological Museum. The holotype, BXGMV0012, is a skull found near Beipiao in a layer of the Sunjiawan Formation probably dating from the Albian. Specimen BXGMV0012-1, a skeleton lacking the skull, discovered in the same quarry as the holotype, was referred to the species.〔 Furthermore a skeleton with skull, displayed by the Sihetun Fossil Museum as a ''Crichtonsaurus bohlini'' specimen, was in 2014 referred to ''Crichtonpelta''. In 2014, Victoria Megan Arbour concluded that ''Crichtonsaurus'' were a ''nomen dubium''. Therefore she named a separate genus for its second species: ''Crichtonpelta''.〔 The generic name combines a reference to Michael Crichton, the author of Jurassic Park, with a Greek πέλτη, ''peltè'', "small shield". At the time this was an invalid ''nomen ex dissertatione''. However in 2015, ''Crichtonpelta'' was validly named by Arbour and Philip John Currie. The type species is ''Crichtonsaurus benxiensis''; the ''combinatio nova'' is ''Crichtonpelta benxiensis''.〔 There was a possibility that, though ''Crichtonsaurus bohlini'' was a ''nomen dubium'', its fossil material in fact belonged to ''Crichtonpelta''. Arbour however, noted clear differences in the scapula and humerus between BXGMV0012-1 and LPM 101, a specimen previously referred to ''Crichtonsaurus bohlini'': the scapula of the former has a tab-like acromion and its humerus a much longer deltopectoral crest.〔 Arbour established several distinguishing traits. One of these was an autapomorphy, unique derived trait: the apex of the (quadrato)jugal, or cheek, horn, is pointing upwards. Also a unique combination of in themselves not unique traits is present. The upper snout armour forms an amorphous mass, not clearly separated into distinctive tiles. The jugal bone is deeper than that of ''Pinacosaurus''. The skull roof is not notched at the lacrimal bone as in ''Pinacosaurus grangeri''. The squamosal horns are shorter than those of ''Pinacosaurus mephistocephalus''. However, these horns are longer and more pointed than those of ''Gobisaurus'' or ''Shamosaurus''. The point of the cheek horn is located on the rear edge. The transverse crest on the top of the rear skull has two points.〔 The holotype of ''Crichtonpelta'' is somewhat larger than ''Crichtonsaurus'', itself about three to four metres long. It is uncertain whether ''Crichtonpelta'' already possessed a tail club.〔 ''Crichtonpelta'' was, within the Ankylosauridae, placed in the Ankylosaurinae, in a basal position.〔 If correct, this makes it the oldest known ankylosaurine.〔 ==References== 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「Crichtonpelta」の詳細全文を読む スポンサード リンク
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