Development and characterization of nine polymorphic microsatellite markers for Mexican spadefoot toads (Spea multiplicata) with cross-amplification in Plains spadefoot toads (S. bombifrons)

We developed nine polymorphic microsatellite markers for the Mexican spadefoot toad, Spea multiplicata. Allele numbers range from five to 12, with observed heterozygosities from 0.48 to 0.87. Because two loci are in linkage disequilibrium, these nine loci provide eight independent markers. Three loci exhibit departure from Hardy-Weinberg equilibrium, possibly resulting from null alleles or population admixture. These markers will be useful for assessing population structure and relatedness in S. multiplicata. Based on our success at cross-amplification in the Plains spadefoot toad (Spea bombifrons), these loci also may be useful in this species with additional optimization.