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''Daqingshanodon'' is an extinct genus of dicynodont therapsid from the Late Permian of Inner Mongolia, China. The type species ''D. limbus'' was described in 1989 from a single skull found in the Naobaogou Formation. ''Daqingshanodon'' belongs to a group of dicynodonts called cryptodonts. It is the smallest known cryptodont, and the only one known from China. Like other cryptodonts, it has a pair of rounded nasal bosses above its nostrils and a ridge of bone on the upper jaw called the postcaniniform process. ''Daqingshanodon'' has a pair of elongated, recurved tusks extending from its beak-like snout. It is distinguished from other dicynodonts by the presence of a distinct ridge running along the side of the skull from below the eye socket to the area around the tusks. The skull of ''Daqingshanodon'' is less than long, yet this specimen is thought to have been an adult on the basis of its well-developed nasal bosses. In his 1998 study of dicynodont biogeography, paleontologist Spencer G. Lucas synonymized ''Daqingshanodon'' with ''Dicynodon'', forming the species ''Dicynodon limbus''. Most of the features used to distinguish ''Daqingshanodon'' as a distinct genus were also seen in specimens of ''Dicynodon''. In 2011, a study of ''Dicynodon'' species included ''D. limbus'' in its phylogenetic analysis. ''D. limbus'' was placed among the cryptodonts, which are only distantly related to ''Dicynodon''. With this phylogenetic placement, the genus ''Daqingshanodon'' was reinstated for ''D. limbus''. Below is a cladogram from the 2011 analysis:〔 |2= }} }} }} }} }} |label2= Dicynodontoidea |2= |2= }} }} }} }} }} }} }} }} ==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「Daqingshanodon」の詳細全文を読む スポンサード リンク
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