Genetic diversity and structure of two endangered mole salamander species of the Trans-Mexican Volcanic Belt

Abstract

The most important factor leading to amphibian population declines and extinctions is habitat degradation and destruction. To help prevent further extinctions, studies are needed to make appropriate conservation decisions in small and fragmented populations. The goal of this study was to provide data from the population genetics of two micro-endemic mole salamanders from the Trans-Mexican Volcanic Belt. Nine microsatellite markers were used to study the population genetics of 152 individuals from two Ambystoma species. We sampled 38 individuals in two localities for A. altamirani and A. rivulare. We found medium to high levels of genetic diversity expressed as heterozygosity in the populations. However, all the populations presented few alleles per locus and genotypes. We found strong genetic structure between populations for each species. Effective population size was small but similar to that of the studies from other mole salamanders with restricted distributions or with recently fragmented habitats. Despite the medium to high levels of genetic diversity expressed as heterozygosity, we found few alleles, evidence of a genetic bottleneck and that the effective population size is small in all populations. Therefore, this study is important to propose better management plans and conservation efforts for these species.