REVIEW OF THE PLIOCENE PECCARIES (ARTIODACTYLA: TAYASSUIDAE) OF NORTH AMERICA

The Pleistocene and Miocene species of flat-heated peccaries (Platygonus) are well known, but the Pliocene species are in a state of taxonomic confusion. Careful analysis of all the available specimens in U.S. museums suggest that there are only two valid species: a smaller species, P. pearcei Gazin 1938, best known from the Hagerman fauna of Idaho, but also found in the Blancan beds of the High Plains (Texas, Oklahoma, Nebraska, Kansas). In addition, it occurs in the Ringold fauna of Washington, in the Blancan of Benson, Arizona, and the Palmetto Mine local fauna of Florida. The type material of P. pearcei consists of a complete articulated adult skeleton and two juvenile articulated skeletons (long on display in the Smithsonian). A much larger species with more bulbous cusps is P. texanus Gidley 1903, which is found only in the Blancan beds of Texas, Oklahoma, Kansas, and Nebraska. It is known from partial skulls and numerous jaws and teeth. The oldest name applied is P. bicalcaratus Cope 1892, based on a non-diagnostic tooth fragment from the Blanco beds that could belong to either taxon. Based on its poor condition, it cannot be definitively assigned to any taxon, so it is a nomen dubium. Analysis of the Pliocene peccary diversity shows that the long-nosed peccary Mylohyus (known from the late Miocene and Pleistocene) must have existed in the North American Pliocene, but so far has not been reported, so it is a ghost lineage. Thus, empirical diversity of Pliocene peccaries must be an underestimate.