A New Species of Plethodontid Salamander from the Jemez Mountains of New Mexico

T account for the occurrence of the lungless salamander Plethodon hardii in the Sacramento Mountains of southern New Mexico, one may assume that the species or its predecessor arrived there via the Rocky Mountains. The country adjacent to the Rockies, except well to the north, is today, so far as is known, uninhabited by these amphibians and probably long has been unsuited to them. It seems plausible that at one time plethodontids existed across the northern part of the continent, dispersing westward from an eastern center of differentiation (Dunn, 1926: 11 and 12). From this northern reservoir one may surmise that they made their way southward, and that at some time they became widespread in the Rockies. Only two species, Plethodon idahoensis of the northern part of the Rocky Mountains in Idaho and P. hardii at the extreme southern end, have been described. It has seemed likely to us that other remnants of a once widely distributed Rocky Mountain fauna might yet exist. On August 14, 1949, motivated by the foregoing idea, we visited the Jemez Mountains, Sandoval County, New Mexico. At the same time we wished to check on the possible occurrence of Eurycea multiplicata (?), reported by Dunn (1926: 316). We failed to find Eurycea but discovered, instead, a Plethodon, which we here describe. We have determined that the material, USNM 42921-2, upon which the record of Eurycea was based, is of this new species.