Fig. 4 in A new genus of tragulid ruminant from the early Miocene of Kenya

Fig. 4. Afrotragulus moruorotensis (Pickford, 2001) and Dorcatherium naui Kaup and Scholl, 1834, type species of each respective genus, late early Miocene of Kenya and Eppelsheim (Germany), respectively. Also below Moschiola meminna Erxleben, 1777 and Hyemoschus aquaticus Ogilby, 1841 (extant tragulids). A. Drawing of A. moruorotensis, m2 of the holotype CMK Mor 1'2000, showing the main characters discussed in the text. B. Drawing of D. naui, m2 of the right mandible of the specimen BMNH M40432 (Eppelsheim; the holotype is lost, see Hillenbrand et al. 2009), showing the main characters discussed in the text. C. Moschiola meminna, left m2 (private collection Jan van der Made, Madrid). D. Hyemoschus aquaticus, right m1 of the specimen MNCN−CSIC 18947. Note the main morphological features that characterize the lower molars of Afrotragulus in occlusal view (A), differentiating it from Dorcatherium (B) and the extant selenodont (C) and bunoselenodont (D) tragulids: enlarged cristids, main cusps with flat internal walls, enlarged and triangular central valley, separated mesial and distal lobes, presence of interlobular bridge that extends between the post−metacristid and the pre−entocristid (note that the lobes in Moschiola are connected though there is no Tragulus−fold present), incomplete "M"−structure, short Dorcatherium−fold. Note also the clear differences in the mesial closing of the trigonid: whereas in Afrotragulus (A) the pre−metacristid and the pre−protocristid extend forward contacting in a marked angle, Dorcatherium (B) presents a hyper−developed and curved pre−protocristid that contacts with a very short pre−metacristid, forming a well developed mesial platform. Drawings not to scale.