Pleistocene climate fluctuations as the major driver of genetic diversity and distribution patterns of the Caspian green lizard, Lacerta strigata Eichwald, 1831

Abstract

Green lizards of the genus Lacerta have served as excellent models for studying the impact of Pleistocene climatic oscillations on genetic structures. The Caspian green lizard, Lacerta strigata , occupies various habitats across the Caucasus and the South Caspian Sea, with the Hyrcanian Forests and north of the Alborz Mountains forming the core of the range. This study aimed to re‐examine the phylogenetic relationships of L. strigata with other congeneric members and to assess the genetic structure and historical demography of the species. Furthermore, Species Distribution Models (SDMs) were performed to infer the species' potential habitat suitability and were then projected on climate scenarios reflecting current and past (6 ky and 21 ky before present) conditions. A total of 39 individuals collected from most of the distribution range, together with additional lacertid species sequences from the GenBank database, were examined using mtDNA (Cyt b and 12S ribosomal RNA) and nuclear (C‐mos and β‐fibrinogen) sequence data. Based on the phylogenetic analyses, L. strigata was found to be a sister taxon to all other members of the genus. The species included two main clades (regional western and eastern) that diverged in a period between the Early and Middle Pleistocene. Based on the BBM and S‐Diva analyses, both dispersal and vicariance events explained the phylogeographic structure of the species in the Hyrcanian Forests. The historical demographic analyses using Bayesian skyline plots showed a mild increase in the effective population size from about 120 Kya for the western regional clade. According to phylogeographic structures and SDMs evidence, as in other species within the region, it appears that the south of the Caspian Sea (Hyrcanian Forests), and the Alborz Mountains acted as multiple refugia during cold periods and promoted expansion outwards amid the warm periods. Overall, the results provided evidence that the genetic structure of the species has been influenced by the Pleistocene climatic fluctuations.

Tracking climate change in the spatial distribution pattern and the phylogeographic structure of Hyrcanian wood frog,Rana pseudodalmatina(Anura: Ranidae)

“…It seems that the presence of two groups of R. pseudodalmatina in the west and east of the distribution may indicate the long-term residence within two different glacial refugia during the Pleistocene. The existence of cryptic refugia and the idea of "refugia-within-refugia" in the Hyrcanian forests that is proposed here for R. pseudodalmatina has been previously discussed for other species that live in this region (Ahmadi et al, 2018;Ahmadzadeh, Flecks, et al, 2013;Saberi-Pirooz et al, 2021). The assessments of demographic history revealed that the recent expansion occurred in the populations (Table 1 and Figure 3).…”

“…The species composition and diversity of the Southwest Asian forests, rich in endemic species, suggests that the Hyrcanian region has likely acted as a glacial refugium for many taxa during the Quaternary glaciations (Röhrig, 1991;Saberi-Pirooz et al, 2018). Phylogeographic studies and climatic models have shown that the southern Caspian Sea has acted as a glacial refugium for a broad range of taxa, including Iranian rock lizards (Darevskia chlorogaster and Darevskia defilippii, Ahmadzadeh, Flecks, et al, 2013), Iranian brown bears (Ursus arctos, Ashrafzadeh et al, 2016), fat dormouse (Glis glis, Ahmadi et al, 2018), Persian mountain salamanders (Paradactylodon persicus, Ahmadzadeh et al, 2020), and Caspian green lizard (Lacerta strigata, Saberi-Pirooz et al, 2021). During the last halfcentury, the climate became warmer in the Hyrcanian forests, with the average annual temperature increasing between 1.28 and 2.45℃ and annual precipitation declining between 55.6 and 409.4 mm (Tohidifar et al, 2016).…”

An integrative insight into the diversity, distribution, and biogeography of the freshwater endemic clade of the Ponticola syrman group (Teleostei: Gobiidae) in the Caucasus biodiversity hotspot

“…A similar effect has been outlined for evolution of several other aquatic species in the south Caspian basin (e.g., Sands et al, 2019 ), including the radiation of Ponticola hircaniaensis (Zarei, Esmaeili, Kovačić, et al, 2022a ) and a possible bottleneck in Proterorhinus nasalis (Zarei, Esmaeili, Schliewen, & Abbasi, 2022b ). Evolution in south Caspian refugia have been also reported for several species in other groups, e.g., rock lizards of the genus Darevskia , Arribas, 1999 (Ahmadzadeh et al, 2013 ; Saberi‐Pirooz et al, 2018 ), the Caspian green lizard Lacerta strigata Eichwald, 1831 (Saberi‐Pirooz et al, 2021 ), the Caucasian pit viper Gloydius halys caucasicus (Nikolsky, 1916) (Asadi et al, 2019 ), the Anatolian mountain frogs of the genus Rana Linnaeus, 1758 (Veith et al, 2003 ), and the freshwater crab Potamon ibericum (de Bieberstein, 1808) (Parvizi et al, 2018 ).…”

“…Evolution in south Caspian refugia have been also reported for several species in other groups, e.g., rock lizards of the genus Darevskia, Arribas, 1999 (Ahmadzadeh et al, 2013;Saberi-Pirooz et al, 2018), the Caspian green lizard Lacerta strigata Eichwald, 1831 (Saberi-Pirooz et al, 2021), the Caucasian pit viper Gloydius halys caucasicus (Nikolsky, 1916) (Asadi et al, 2019), the Anatolian mountain frogs of the genus Rana Linnaeus, 1758 (Veith et al, 2003), and the freshwater crab Potamon ibericum (de Bieberstein, 1808) (Parvizi et al, 2018).…”

Morphological variation and its correlation with bioclimatic factors in Odorrana graminea sensu stricto

“…Phenotypic variation is the raw material for natural selection through which fitness is optimized via effects on survival and reproduction (van Buskirk et al, 1997). Climate is an important factor affecting the biogeographical distribution and species evolution (Li et al, 2016;Saberi-Pirooz et al, 2021). The phenotypic variation in vertebrates is generally associated with climatic factors, especially in ectotherms, through such factors as the effects of temperature and precipitation on body size (Wen and Fu, 2020), body shape (Gvodk et al, 2010), and head traits (Rainha et al, 2021) in amphibians and scale number (Wegener et al, 2014) and head traits (Jaffe et al, 2016) in reptiles.…”