Identification and Distribution of the Peromyscus Leucopus Species Group in East Texas

Abstract

The utility of external and cranial measurements to distinguish between specimens of Peromyscus leucopus and P. gossypinus from East Texas was assessed. The extent of age, sexual, and individual variation was statistically evaluated in each species. No significant secondary sexual dimorphism was evident, but age variation was significant in both species. Difficulty in identifying certain individuals was circumvented when age was taken into account. Univariate and multivariate statistical analyses were used to determine the identity of specimens previously regarded as hybrids between gossypinus and leucopus by McCarley (1954). Results indicate these specimens are not intermediate in cranial morphology and, consequently, it is doubtful that they represent "natural hybrids." The distribution of leucopus and gossypinus in East Texas is redefined based on correct identification of specimens.