A new species of groundsnake genus Atractus Wagler, 1828 (Serpentes, Dipsadidae) from the Peruvian Andes revealed by unequivocal morphological characters

Abstract

Based on an exhaustive revision of external morphological characters we describe a new species of Atractus from the humid montane forest of the Andes of northern Peru, Cajamarca department, occurring at elevations of 1641 to 2161 m. This new species was misidentified as A. gigas in the literature and for more than a decade represented the southernmost record of the that species. In the absence of molecular data and limited by a small sample, we use some underreported characters in the genus Atractus such as the presence of apical pits. Thus, the combination of apical pits as well as other characters mentioned in the literature (i.e., head scutellation and number of subcaudals) distinguishes the Peruvian population from A. gigas, and strongly supports the morphological separation of this taxon from the rest of its congeners.