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''Kaprosuchus'' is an extinct genus of mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Greek κάπρος, ''kapros'' ("boar") and σοῦχος, ''souchos'' ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar. It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ''ZooKeys'' in 2009 along with other Saharan crocodyliformes such as ''Anatosuchus'' and ''Laganosuchus''.〔Associated Press (November 19, 2009). (3 new ancient crocodile species fossils found ). Yahoo News.〕 The type species is ''K. saharicus''. ==Description== ''Kaprosuchus'' is known from a nearly complete skull 507 mm in length in which the lower jaw measured 603 mm long, whilst the entire animal is originally estimated to have been around in length,〔〔National Geographic. November 2009. p. 140-141〕 but later comparisons to similar crocodiles suggest a total estimated body length approximately .〔(【引用サイトリンク】url=http://www.prehistoric-wildlife.com/species/k/kaprosuchus.html )〕 It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits into notches in upper jaw. This type of dentition is not seen in any other known crocodyliform. Another unique characteristic of ''Kaprosuchus'' is the presence of large, rugose horns formed from the squamosal and parietal bones that project posteriorly from the skull. Smaller projections are also seen in the closely related ''Mahajangasuchus''. The snout of ''Kaprosuchus'' shows generalized proportions and the naris is positioned dorsally. In ''Kaprosuchus'' many teeth are hypertrophied and labiolingually (laterally) compressed, unlike those of crocodyliforms with similarly shallow snouts, which are usually subconical and of moderate length. Another difference between the skull of ''Kaprosuchus'' and those of crocodyliforms that also possess dorsoventrally compressed snouts is the great depth of the posterior portion of the skull. In ''Kaprosuchus'', the orbits (i.e., eye sockets) open laterally and are angled slightly forward rather than upward. The orbits turned forward suggest that there was somewhat stereoscopic vision, i.e., an overlap in the visual field of the animal.〔 The surfaces of the premaxillae are rugose with the edges elevated above the body of the bone, suggesting that a keratinous shield would have been supported by the rugosities at the tip of the snout. Along the interpremaxillary suture, the area where the two premaxillae meet, the surface is smooth, giving the paired rugosity of the premaxillae the resemblance of a moustache in anterior view.〔 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「Kaprosuchus」の詳細全文を読む スポンサード リンク
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