Abstract:
New fossils of the pinnipediform Pteronarctos from the Miocene Astoria Formation of coastal Oregon provide more information on the cranial anatomy, interrelationships, and higher level phylogeny of this taxon. Additional skulls are referred to a previously described species, P. goedertae (Barnes, 1989). A previously named species, Pteronarctos piersoni (Barnes, 1990) is recognized as the junior synonym of P. goedertae. The genus Pacificotaria (Barnes, 1992) is synonymized with Pteronarctos. The genus Pteronarctos is removed from the "Enaliarctinae" (= "Enaliarctidae") and recognized as the sister group of the Pinnipedia (including Otariidae, Odobenidae, Allodesmus, Desmatophoca, Pinnarctidion, and Phocidae).