A New Genus of Hesperhyine Peccary (artiodactyla: Tayassuidae) from the Late Oligocene of Oregon

”Thinohyus” osmonti was based on a nearly complete skull and jaws (UCMP 393) found in the upper John Day beds (upper Oligocene) of Oregon, and named by W.J. Sinclair in 1905. Since its discovery, it has been transferred from one primitive peccary genus to another (Thinohyus, Bothrolabis, Perchoerus), without a careful examination of the excellent fossils. It is not referable to Thinohyus from the John Day beds, since it has a much more advanced skull, with a narrow rostrum and shallow facial vacuities, not the convex conical rostrum found in Thinohyus and more primitive peccaries. It was assigned to that genus only because its teeth are the same size and it came from the same beds. Careful re-examination of the skull shows that it has the diagnostic plesiochoanal fossa found only in the newly recognized subfamily Hesperhyinae, as well as other derived characters of that group. It is a relatively primitive member of that group (in the same trichotomy as Stuckyhyus siouxensis and Floridachoerus olseni) consistent with its temporal placement in the late Arikareean. It belongs in a new genus, here designated Fremdohyus.