E.N. Solovyeva

Molecular differentiation and taxonomy of the sunwatcher toad-headed agama species complex Phrynocephalus superspecies helioscopus (Pallas 1771) (Reptilia: Agamidae)

Lizards of the sunwatcher toad-headed agama species complex Phrynocephalus superspecies helioscopus, mostly distributed in Central Asia and Middle East, were examined using analysis of variation at the mitochondrial cytochrome oxidase c subunit I gene fragment and fingerprint analysis of nuclear DNA (inter-SINE PCR technique). A total of 86 individual tissue samples from 53 populations, to the full extent representing different parts of the species complex range, were subjected to molecular genetic examination, and surprisingly deep differentiation was revealed. The populations analyzed split into 12 isolated phylogroups, many of which were characterized by a narrow range and genetic isolation. Monophyly of sunwatcher (Ph. helioscopus) and Persian (Ph. persicus) toad-headed agamas was confirmed. However, both of these species probably represent the species complexes. Zoogeography of Central Asiais discussed.

Phylogenetic relationships and subgeneric taxonomy of toad-headed agamas Phrynocephalus (Reptilia, Squamata, Agamidae) as determined by mitochondrial DNA sequencing

119 Toaddheaded agamas (Phrynocephalus) is an essenn tial element of arid biotopes throughout the vast area spanning the countries of Middle East and Central Asia. They constitute one of the most diverse genera of the agama family (Agamidae), variously estimated to comprise 26 to 40 species [1]. The subgeneric Phrynoo cephalus taxonomy is poorly studied: recent taxoo nomic revision have been conducted without analysis of the entire genus diversity [1]; therefore, its phylogee netic position within Agamidae family remains unclear [2–5]. There were several attempts to reconn struct the phylogeny of this genus [4–10]. Reconn struction on the basis of the morphological traits is diff ficult because of high intraspecific morphological variation of the toaddheaded agamas and because of prevalence of substrate races, the morphs confined to specific substrates [11]. At the same time, the phylogee netic schemes on the basis of molecular data [4, 5, 10] are incomplete: they have been obtained on a small sample of species, and the genetic markers used were insufficiently informative. To clarify the main patterns of herpetofauna differr entiation in arid Eurasian areas, we studied phylogee netic relationships between 37 agama taxa encompasss ing about 80% of the known Phrynocephalus species and all the main species groups. The resultant scheme makes it possible to revise the subgeneric taxonomy of toaddheaded agamas and to clarify the positions of some morphs. Tissue samples of 52 Phrynocephalus specimens and eight closely related agamas from the Agaminae subfamily (the genera Laudakia, Paralaudakia, Trapelus, and Stellagama) were used in molecular genetic analysis. In total, 69 sequences from the Genn Bank were studied, 28 of which served as outgroups (the members of Agamidae, Chamaeleonidae, Iguanidae, and Lacertidae). The fragment sequences of the following four mitochondrial DNA genes were used in phylogenetic analysis: the genes of subunit I of cytochrome c oxii dase (COI), of subunits II and IV of NADHHdehydroo genase (ND2 and ND4), and of cytochrome b (cyt b). The overall length of alignment was 2703 bp (Genn Bank numbers HQ919083; HM915020; and KF6916166KF691738, see table). The algorithms of the maximum likelihood (ML), maximum parsimony (MP), and Bayesian analysis (UBA) for the concatee nated sequences of the four genes were used in analyy sis. To assess the level of genetic differentiation between taxa, the average uncorrected pdistances were calculated. The figure shows the dendrograms obtained. There is considerable topological similarity between the phylogenetic schemes for nucleotide and amino …

Molecular and morphological differentiation of Secret Toad-headed agama, Phrynocephalus mystaceus, with the description of a new subspecies from Iran (Reptilia, Agamidae)

Abstract The morphological and genetic variation of a wide-ranging Secret Toad-headed agama, Phrynocephalus mystaceus that inhabits sand deserts of south-eastern Europe, Middle East, Middle Asia, and western China is reviewed. Based on the morphological differences and high divergence in COI (mtDNA) gene sequences a new subspecies of Ph. mystaceus is described from Khorasan Razavi Province in Iran. Partial sequences of COI mtDNA gene of 31 specimens of Ph. mystaceus from 17 localities from all major parts of species range were analyzed. Genetic distances show a deep divergence between Ph. mystaceus khorasanus ssp. n. from Khorasan Razavi Province and all other populations of Ph. mystaceus. The new subspecies can be distinguished from other populations of Ph. mystaceus by a combination of several morphological features. Molecular and morphological analyses do not support the validity of other Ph. mystaceus subspecies described from Middle Asia and Caspian basin. Geographic variations in the Ph. mystaceus species complex and the status of previously described subspecies were discussed.

Cenozoic aridization in Central Eurasia shaped diversification of toad-headed agamas (Phrynocephalus; Agamidae, Reptilia)

We hypothesize the phylogenetic relationships of the agamid genus Phrynocephalus to assess how past environmental changes shaped the evolutionary and biogeographic history of these lizards and especially the impact of paleogeography and climatic factors. Phrynocephalus is one of the most diverse and taxonomically confusing lizard genera. As a key element of Palearctic deserts, it serves as a promising model for studies of historical biogeography and formation of arid habitats in Eurasia. We used 51 samples representing 33 of 40 recognized species of Phrynocephalus covering all major areas of the genus. Molecular data included four mtDNA (COI, ND2, ND4, Cytb; 2,703 bp) and four nuDNA protein-coding genes (RAG1, BDNF, AKAP9, NKTR; 4,188 bp). AU-tests were implemented to test for significant differences between mtDNA- and nuDNA-based topologies. A time-calibrated phylogeny was estimated using a Bayesian relaxed molecular clock with nine fossil calibrations. We reconstructed the ancestral area of origin, biogeographic scenarios, body size, and the evolution of habitat preference. Phylogenetic analyses of nuDNA genes recovered a well-resolved and supported topology. Analyses detected significant discordance with the less-supported mtDNA genealogy. The position of Phrynocephalus mystaceus conflicted greatly between the two datasets. MtDNA introgression due to ancient hybridization best explained this result. Monophyletic Phrynocephalus contained three main clades: (I) oviparous species from south-western and Middle Asia; (II) viviparous species of Qinghai–Tibetan Plateau (QTP); and (III) oviparous species of the Caspian Basin, Middle and Central Asia. Phrynocephalus originated in late Oligocene (26.9 Ma) and modern species diversified during the middle Miocene (14.8–13.5 Ma). The reconstruction of ancestral areas indicated that Phrynocephalus originated in Middle East–southern Middle Asia. Body size miniaturization likely occurred early in the history of Phrynocephalus. The common ancestor of Phrynocephalus probably preferred sandy substrates with the inclusion of clay or gravel. The time of Agaminae radiation and origin of Phrynocephalus in the late Oligocene significantly precedes the landbridge between Afro-Arabia and Eurasia in the Early Miocene. Diversification of Phrynocephalus coincides well with the mid-Miocene climatic transition when a rapid cooling of climate drove progressing aridification and the Paratethys salinity crisis. These factors likely triggered the spreading of desert habitats in Central Eurasia, which Phrynocephalus occupied. The origin of the viviparous Tibetan clade has been associated traditionally with uplifting of the QTP; however, further studies are needed to confirm this. Progressing late Miocene aridification, the decrease of the Paratethys Basin, orogenesis, and Plio–Pleistocene climate oscillations likely promoted further diversification within Phrynocephalus. We discuss Phrynocephalus taxonomy in scope of the new analyses.