Werner, F. (1930) - Description of Podarcis gaigeae gaigeae. - In: “Contribution to the knowledge of the reptiles and amphibians of Greece, especially the Aegean islands”. Occasional papers of the Museum of Zoology, University of Michigan, 211: 1-46.  Mayer, W. & Tiedemann, F. (1980) - Elektrophoretische Untersuchungen an europäischen Arten der Gattungen Lacerta und Podarcis. I. Die Podarcis-Formen der griechischen Inseln Milos und Skiros. - Journal of Zoological Systematics and Evolutionary Research, Berlin, 18 (2): 147-152.  × Anhand proteinelektrophoretischer Daten über 18 Genloci wurden Kleinlacerten der griechischen Inseln Milos und Skiros mit Festiandspopulationen von Podarcis taurica ionica, Podarcis muralis albanica und Podarcis erhardii verglichen. Die Genfrequenzen der polymorphen Loci werden ange-geben und die genetischen Distanzen nach Neierrechnet. Die Größen der genetischen Distanzen werden diskutierc und Podarcis milensis als Art bestätigt. Die Populationen von Milos und Skiros erwiesen sich als nächstverwandt, beide sind in die nahe Verwandtschaft von Podarcis taurica und nicht von Podarcis muralis zu stellen. Tiedemann, F. & Mayer,W. (1980) - Ein Beitrag zur systematischen Stellung der Skyroseidechse. - Annalen des Naturhistorischen Museums in Wien, 83: 543-546. Valakos, E.D. & Kourkouli, A. & Skopeliti, M. & Pafilis, P. & Poulakakis, N. & Voutsas, I.F. & Lymberakis, P.L.& Simou, C. & Voelter, W. & Tsitsilonis, O.E. (2007) - Combining immunological and molecular data to assess phylogenetic relations of some Greek Podarcis species. - Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 147 (1): 1-10. × Most recent molecular studies revealed the phylogeny of Greek Podarcis species, which for years remained elusive, due to discordant data
produced from various chromosomal, complement fixation and protein studies. In this report, we analyzed cellular immune responses of spleen-
derived lymphocytes from six allopatric Podarcis species encountered in Greece, by assessing two-way mixed lymphocyte reaction (MLR)-
induced proliferation. On the basis of stimulation indices (S.I.) as determined from cultures set up from xenogeneic splenocytes coincubated in
pairs, we generated a phylogenetic tree, fully consistent with the phylogenetic relationships of Podarcis as determined by parallel analyses based
on partial mitochondrial (mt) DNA sequences. Although the exact mechanisms triggering lymphocyte responses in lizard two-way xenogeneic
MLR are not fully understood, our results show the potential use of cell-mediated immune responses as an additional approach to mtDNA
analysis, for species delimitation within specific lizard taxa. Runemark, A. & Hansson, B. & Pafilis, P. & Valakos, E.D. Svensson, E.I. (2010) - Island biology and morphological divergence of the Skyros wall lizard Podarcis gaigeae: a combined role for local selection and genetic drift on color morph frequency divergence? - Evolutionary Biology, 10: 269 × Background: Patterns of spatial variation in discrete phenotypic traits can be used to draw inferences about the
adaptive significance of traits and evolutionary processes, especially when compared to patterns of neutral genetic
variation. Population divergence in adaptive traits such as color morphs can be influenced by both local ecology
and stochastic factors such as genetic drift or founder events. Here, we use quantitative color measurements of
males and females of Skyros wall lizard, Podarcis gaigeae, to demonstrate that this species is polymorphic with
respect to throat color, and the morphs form discrete phenotypic clusters with limited overlap between categories.
We use divergence in throat color morph frequencies and compare that to neutral genetic variation to infer the
evolutionary processes acting on islet- and mainland populations.
Results: Geographically close islet- and mainland populations of the Skyros wall lizard exhibit strong divergence in
throat color morph frequencies. Population variation in throat color morph frequencies between islets was higher
than that between mainland populations, and the effective population sizes on the islets were small (Ne:s < 100).
Population divergence (FST) for throat color morph frequencies fell within the neutral FST-distribution estimated
from microsatellite markers, and genetic drift could thus not be rejected as an explanation for the pattern.
Moreover, for both comparisons among mainland-mainland population pairs and between mainland-islet
population pairs, morph frequency divergence was significantly correlated with neutral divergence, further pointing
to some role for genetic drift in divergence also at the phenotypic level of throat color morphs.
Conclusions: Genetic drift could not be rejected as an explanation for the pattern of population divergence in
morph frequencies. In spite of an expected stabilising selection, throat color frequencies diverged in the islet
populations. These results suggest that there is an interaction between selection and genetic drift causing
divergence even at a phenotypic level in these small, subdivided populations.
Runemark, A. & Hey, J. & Hansson, B. & Svensson, E.I. (2012) - Vicariance divergence and gene flow among islet populations of an endemic lizard. - Molecular Ecology, 21 (1): 117-129. × Allopatry and allopatric speciation can arise through two different mechanisms: vicariance or colonization through dispersal. Distinguishing between these different allopatric mechanisms is difficult and one of the major challenges in biogeographical research. Here, we address whether allopatric isolation in an endemic island lizard is the result of vicariance or dispersal. We estimated the amount and direction of gene flow during the divergence of isolated islet populations and subspecies of the endemic Skyros wall lizard Podarcis gaigeae, a phenotypically variable species that inhabits a major island and small islets in the Greek archipelago. We applied isolation-with-migration models to estimate population divergence times, population sizes and gene flow between islet-mainland population pairs. Divergence times were significantly correlated with independently estimated geological divergence times. This correlation strongly supports a vicariance scenario where islet populations have sequentially become isolated from the major island. We did not find evidence for significant gene flow within P. g. gaigeae. However, gene-flow estimates from the islet to the mainland populations were positively affected by islet area and negatively by distance between the islet and mainland. We also found evidence for gene flow from one subspecies (P. g. weigandi) into another (P. g. gaigeae), but not in the other direction. Ongoing gene flow between the subspecies suggests that even in this geographically allopatric scenario with the sea posing a strong barrier to dispersal, divergence with some gene flow is still feasible. Psonis, N. & Antoniou, A. & Kukushkin, O. & Jablonski, D. & Petrov, B. & Crnobrnja-Isailovic, J. & Sotiropoulos, K. & Gherghel, I. & Lymberakis, P. & Poulakakis, N. (2017) - Hidden diversity in the Podarcis tauricus (Sauria, Lacertidae) species subgroup in the light of multilocus phylogeny and species delimitation. - Molecular Phylogenetics and Evolution, 106: 6-17. × The monophyletic species subgroup of Podarcis tauricus is distributed in the western and southern parts of the Balkans, and includes four species with unresolved and unstudied inter- and intra-specific phylogenetic relationships. Using sequence data from two mitochondrial and three nuclear genes and applying several phylogenetic methods and species delimitation approaches to an extensive dataset, we have reconstructed the phylogeny of the Podarcis wall lizards in the Balkans, and re-investigated the taxonomic status of the P. tauricus species subgroup. Multilocus analyses revealed that the aforementioned subgroup consists of five major clades, with P. melisellensis as its most basal taxon. Monophyly of P. tauricus sensu stricto is not supported, with one of the subspecies (P. t. ionicus) displaying great genetic diversity (hidden diversity or cryptic species). It comprises five, geographically distinct, subclades with genetic distances on the species level. Species delimitation approaches revealed nine species within the P. tauricus species subgroup (P. melisellensis, P. gaigeae, P. milensis, and six in the P. tauricus complex), underlining the necessity of taxonomic re-evaluation. We thus synonymize some previously recognized subspecies in this subgroup, elevate P. t. tauricus and P. g. gaigeae to the species level and suggest a distinct Albanian-Greek clade, provisionally named as the P. ionicus species complex. The latter clade comprises five unconfirmed candidate species that call for comprehensive studies in the future. Psonis, N. & Antoniou, A. & Karameta, E. & Leaché, A.D. & Kotsakiozi, P. & Darriba, D. & Kozlov, A. & Stamatakis, A. & Poursanidis, D. & Kukushkin, O. & Jablonski, D. & Crnobrnja–Isailović, J. & Gherghel, I. & Lymberakis, P. & Poulakakis, N. (2018) - Resolving complex phylogeographic patterns in the Balkan Peninsula using closely related wall-lizard species as a model system. - Molecular Phylogenetics and Evolution, 125: 100-115. × The Balkan Peninsula constitutes a biodiversity hotspot with high levels of species richness and endemism. The complex geological history of the Balkans in conjunction with the climate evolution are hypothesized as the main drivers generating this biodiversity. We investigated the phylogeography, historical demography, and popula- tion structure of closely related wall-lizard species from the Balkan Peninsula and southeastern Europe to better understand diversification processes of species with limited dispersal ability, from Late Miocene to the Holocene. We used several analytical methods integrating genome-wide SNPs (ddRADseq), microsatellites, mitochondrial and nuclear DNA data, as well as species distribution modelling. Phylogenomic analysis resulted in a completely resolved species level phylogeny, population level analyses confirmed the existence of at least two cryptic evolutionary lineages and extensive within species genetic structuring. Divergence time estimations indicated that the Messinian Salinity Crisis played a key role in shaping patterns of species divergence, whereas in- traspecific genetic structuring was mainly driven by Pliocene tectonic events and Quaternary climatic oscillations. The present work highlights the effectiveness of utilizing multiple methods and data types coupled with extensive geographic sampling to uncover the evolutionary processes that shaped the species over space and time.
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