Isolation and characterization of 10 tetranucleotide microsatellites in the Grassland Earless Dragon (Tympanocryptis pinguicolla)

The endangered Grassland Earless Dragon (Tympanocryptis pinguicolla) exists only in fragmented populations separated by agricultural and urban landscapes. To provide the tools for estimating the genetic structure and dispersal characteristics critical for the proper management of this species, we isolated and tested 10 tetranucleotide polymorphic microsatellite markers. The loci were highly polymorphic when tested on 32 individuals from one population showing seven to 18 alleles. The values of both the observed and the expected heterozygosities ranged from 0.350 to 0.938 and from 0.710 to 0.880, respectively. We detected no linkage disequilibrium among these loci following Bonferroni correction, however, one locus (ED2G3) consistently violated Hardy-Weinberg expectations when tested on natural populations and is expected to have null alleles. A second locus (ED2H5) was found to violate Hardy-Weinberg expectations in one population but not in others and will require evaluation more broadly. In summary, we have developed eight or nine markers to study the fine-scale population genetics of Tympanocryptis pinguicolla in the ACT.