A reinvestigation of phylogeny and divergence times of the Ablepharus kitaibelii species complex (Sauria, Scincidae) based on mtDNA and nuDNA genes

Abstract Morphological and DNA data support that the East Mediterranean snake-eyed skink Ablepharus kitaibelii represents a species complex that includes four species A. kitaibelii , A. budaki , A. chernovi , and A. rueppellii , highlighting the need of its taxonomic reevaluation. Here, we used Bayesian and Maximum Likelihood methods to estimate the phylogenetic relationships of all members of the complex based on two mitochondrial (cyt b , 16S rRNA) and two nuclear markers (MC1R, and NKTR) and using Chalcides, Eumeces , and Eutropis as outgroups. The biogeographic history of the complex was also investigated through the application of several phylogeographic (BEAST) and biogeographic (BBM) analyses. Paleogeographic and paleoclimatic data were used to support the inferred phylogeographic patterns. The A. kitaibelli species complex exhibits high genetic diversity, revealing cases of hidden diversity and cases of non-monophyletic species such as A. kitaibelii and A. budaki . Our results indicate that A. pannonicus branches off first and a group that comprises specimens of A. kitaibelli and A. budaki from Kastelorizo Island group (southeast Greece) and southwest Turkey, respectively is differentiated from the rest A. kitaibelli and A. budaki populations and may represent a new species. The estimated divergence times place the origin of the complex in the Middle Miocene (∼16 Mya) and the divergence of most currently recognized species in the Late Miocene. The inferred ancestral distribution suggests that the complex originated in Anatolia, supposing that several vicariance and dispersal events that are related with the formation of the Mid-Aegean Trench, the Anatolian Diagonal and the orogenesis of the mountain chains in southern and eastern Anatolia have led to current distribution pattern of A. kitaibelii species complex in the Balkans and Middle East.