Systematics of the Pseudoeurycea Bellii (Caudata: Plethodontidae) Species Complex

Abstract

Salamanders of the Pseudoeurycea bellii complex are widespread in Me´ xico north and west of the Isthmus of Tehuantepec. They are the largest terrestrial salamanders and have distinctive color patterns consisting of a general black ground color with strikingly bold red-orange marks in different patterns on the dorsal surface. At present three species are recognized: P. bellii (widespread, with two subspecies), P. gigantea (restricted to a small area of eastern Me´ xico), and P. naucampatepetl (known only from the vicinity of the type locality in west-central Veracruz). A phylogenetic analysis based on two mitochondrial genes (cytochrome b and 16S RNA) finds support for three main clades, one including P. gigantea and P. naucampatepetl, another including the Oaxacan samples, and a third including P. bellii. New morphological data, DNA sequences, and limited allozymic information provide evidence that the Oaxacan clade comprises two species. The name P. boneti is resurrected from synonymy and applies to northern Oaxacan populations, while a new species is described from extreme western Oaxaca at elevations lower than have been recorded elsewhere for members of the complex.