Anatomical Revision of the Genusmerycopotamus(artiodactyla; Anthracotheriidae): Its Significance for Late Miocene Mammal Dispersal in Asia

New fossil remains of the anthracothere genusMerycopotamusFalconer and Cautley, are described. Most of them were discovered by the Harvard University and Geological Survey of Pakistan joint research project (Y‐GSP) in the well‐dated Middle and Late Miocene deposits of the Potwar Plateau in northern Pakistan. This new material led us to revise the systematics of the genus with the validation of three species,M. nanusFalconer (M. pusillusLydekker),M. dissimilisFalconer and Cautley, andM. medioximusLihoreauet al., and allowed us to determine precisely their chronological distributions in a continuous Neogene sequence. Other specimens reported from the late Miocene deposits of the Khorat Plateau in north‐east Thailand by the Department of Mineral Resources are the first remains ofMerycopotamusto have been discovered in that region and are attributed toM. medioximus. These discoveries indicate a wider geographical distribution of the genus in the early Late Miocene. Anatomical investigations highlight the evolution ofMerycopotamusthrough the Miocene towards more amphibious habits. Palaeobiogeographical and palaeoecological information forMerycopotamusstress the role of the Himalayan orogenesis as a dispersal barrier and the impact of a major global regression event on the evolution of Indian Subcontinent faunas from the Middle Miocene to the Late Pliocene.