New material of P alaeoamasia kansui ( E mbrithopoda, M ammalia) from the E ocene of T urkey and a phylogenetic analysis of E mbrithopoda at the species level

Since the discovery of the megaherbivore A rsinoitherium zitteli B eadnell (early O ligocene of E gypt), the extinct order E mbrithopoda has remained an enigmatic group, with disputed affinities among ungulates. In this study, new specimens of P alaeoamasia kansui from the early P alaeogene of T urkey are described and a synthetic dental terminology is proposed for embrithopods. Based on 130 cranial–mandibular and dental characters, the first phylogenetic analysis of embrithopods is carried out in aim to enhance the position of P alaeoamasia within embrithopods. The monophyly of E mbrithopoda is confirmed, following the topology ( P henacolophus ( N amatherium ( A rsinoitheriinae, P alaeamasiinae))). However, phylogenetic relationships between E urasian embrithopods ( P alaeoamasiinae: P alaeoamasia , C rivadiatherium and H ypsamasia ) remain unresolved. The integration of all embrithopod genera within a cladistic analysis encompassing a wider taxonomic sample ( C ondylarthra, A frotheria/ P aenungulata and L aurasiatheria) also supports E mbrithopoda as being monophyletic, but questions the position of both P henacolophus and N amatherium within E mbrithopoda. Finally, possible faunal exchange events are proposed based on three hypothesized scenarios between E urasia and A rabia– A frica during the early P alaeogene.