ИСТИНА

Phrynocephalus is one of the largest genera of Agamidae family, but it`s taxonomy is still far from being clear. The genus consists of 26–50 species, with many lineages having an uncertain status. We obtained 275 sequences of COI gene and reconstructed phylogenetic dendrograms in MrBayes (BA) and Treefinder (ML). Species delimitation was performed using bGMYC (Bayesian General Mixed Yule Coalescent), ABGD (Automatic Barcode Gap Discovery), PTP (Puasson Tree Processes) under hs (heuristic search), and ML (maximim likelihood). Uncorrected p-distances were calculated in MEGA. Our results demonstrate a high level of cryptic diversity within Phrynocephalus, with 54 to 75 species being detected by species delimitation algorithms. However, these numbers seem to be overestimated and influenced by algorithm sensitivity and hence more likely represent the numbers of subspecies rather than species. According to our results, the most realistic is ABGD, PTP hs is, on the contrary, the most fragmentizing method. Algorithms used in this study have proved to be good for preliminary analysis of group diversity. They allowed us to discover high levels of divergence in several species complexes and to automatically detect phylogenetic lineages having potentially subspecific status. For some species, the number of such lineages is especially high: Ph. interscapularis, Ph. scutellatus, Ph. ocellatus etc. Frequency distribution of uncorrected p-distances shows the gap of 5% between subspecies and species and the gap of 9% between species complexes.