COI-Barcoding and Species Delimitation Assessment of Toad-Headed Agamas of the Genus Phrynocephalus (Agamidae, Squamata) Reveal Unrecognized Diversity in Central Eurasia

We provide a diversity assessment of the agamid genus Phrynocephalus Kaup, 1825. analyze COI mtDNA barcodes from 385 individuals sampled all over range. apply ABGD, ASAP, bGMYC, mlPTP and hsPTP species delimitation algorithms to gene fragment variation assess in Phrynocephalus. Nine groups are revealed agreement with earlier studies on phylogenetic relationships genus. demonstrate that present taxonomy likely underestimates actual Alternative confusingly wide range possible number species—from 54 103 MOTUs (molecular operational taxonomic units). The ASAP scheme recognizing 63 most closely fits currently recognized framework also report 13 previously unknown lineages as unverified candidate species. ABGD reflect Phrynocephalus, while largely overestimate it. argue these lizards based exclusively markers is insufficient, call for further integrative joining data morphology, nuDNA fully stabilize lizards.