Genetic variation and admixture of red-eared sliders (Trachemys scripta elegans) in the USA

Publication date: Available online 23 December 2019Source: Molecular Phylogenetics and EvolutionAuthor(s): James F. Parham, Theodore J. Papenfuss, Anna B. Sellas, Bryan L. Stuart, W. Brian SimisonAbstractThe most ubiquitous, abundant, and invasive turtle on Earth, Trachemys scripta elegans (TSE, “red-eared slider”), is one of four taxa in a clade that is native to the USA and adjacent Mexico (three subspecies of Trachemys scripta plus Trachemys gaigeae). The present range-wide study of this clade is based on 173 known-locality mtDNA sequences combined with ddRAD libraries for 43 samples emphasizing the western part of the range of TSE and its contact with that of T. gaigeae and anthropogenic hybrids between TSE and T. s. scripta. The data presented here are the first to sample the TSE x T. s. scripta intergrade zone or TSE x T. s. scripta crosses from introduced turtles. In the western part of its range (New Mexico and Texas), most samples of TSE from the Pecos River have mtDNA haplotypes matching T. gaigeae. Structure analysis of SNPs from the ddRAD show evidence of genetic admixture between T. gaigeae and TSE in all included samples from the Rio Grande and Pecos River. These populations also exhibit T. gaigeae-like head stripes, i.e., a postorbital marking that does not reach the eye. The genetic and morphological data are thereby reconciled, as both suggest that these TSE are intergrades. We recommend that these populations continue to be considered TSE, despite the ad...
Source: Molecular Phylogenetics and Evolution - Category: Molecular Biology Source Type: research