Genetic variability of the tokay gecko based on mitochondrial and nuclear DNA.

With largely allopatric distribution, the black tokay and the red tokay are two distinct morphs of the subspecies Gekko gecko gecko. In consideration of their different morphological characteristics, the taxonomic status of G. g. gecko is disputed. Through detailed morphological comparison, it has been proposed that the black tokay should be elevated to species ranking, but without strong genetic evidence. In order to further investigate the taxonomic status of the tokay gecko (G. gecko), we used one mitochondrial marker (ND2) and three nuclear markers (RAG1, c-mos, and ITS2) to explore the phylogenetic and taxonomic relationship of the tokay gecko. Our results revealed a deep phylogeographical divergence in tokay gecko and at the same time provided us with the evidence of possible introgressive hybridization or/and incomplete lineage sorting between the black tokay and the red tokay. The elevation of the black tokay to species level is also supported by our results. However, due to limited sampling and genetic data, this elevation should be further corroborated by more genetic evidence.