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''Carodnia'' is an extinct genus of South American ungulate known from the Paleocene of Brazil and Argentina, and the Eocene of Peru. ''Carodnia'' is placed in the order Xenungulata together with ''Etayoa'' and ''Notoetayoa''. ''Carodnia'' is the largest mammal known from the Paleocene of South America. It was heavily built and had large canines and cheek teeth with a crested pattern like the uintatheres to which it can be related.〔 In life, it would have been a tapir-sized animal. It bore strong resemblances to dinoceratans, although without tusks or ossicones. ==Description== Simpson noted that ''Carodnia'' resembles the primitive unitathere ''Probathyopsis''. Although Paula Couto also made the same favourable comparison, he placed ''Carodnia'' in the new order Xenungulata. concluded that ''Probathyopsis'' shares several dental characteristics with ''Carodnia'', but that in the latter the anterior dentition of is more reduced, the second lower and upper premolars are enlarged and pointed, and that the first and second molars are more lophodont. Gingerich thought the differences could justify a separate family for ''Carodnia'' but proposed that it should be included in ''Probathyopsis''. grouped ''Carodnia'' with Pyrotheria but later concluded that this was a mistake. ''Carodnia'' is characterized by bilophodont〔A loph is a crest on the crown of a tooth. A bilophodont tooth has two parallel lophs running transversally across the tooth.〕 first and second molars and more complex lophate〔 third molars, which suggests possible links to pyrotheres, uintatheres, and even arctocyonids. The bones of the foot are short and robust and the digits terminate in broad, flat, and unfissured hoof-like unguals, unlike any other known meridiungulate. ''C. feruglioi'' and ''C. cabrerai'' (from the Riochican SALMA of Patagonia)〔 are known from only a few dental remains. ''C. vieirai'' (from the Itaboraian SALMA of Itaborai)〔 is known from much more complete dental, cranial, and postcranial remains including an almost complete mandible, many vertebrae, and several partial leg bones. When first described ''Carodnia'' and ''Ctalecarodnia'', the former was known only from a left lower molar which was lacking in the latter, making a comparison very difficult. , based on considerably more complete remains, concluded that the molars and premolars of both are indistinguishable and therefore reduced ''Ctalecarodnia'' to a synonym. Paula Couto also noted that the dentition of ''C. cabrerai'' and ''C. feruglioi'' are similar except in size, and that ''C. feruglioi'' can be a juvenile ''C. cabrerai'', but nevertheless left them as two distinct species. 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「Carodnia」の詳細全文を読む スポンサード リンク
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