| Lacerta mixta MÉHELY, 1909 Lacerta composita MÉHELY, 1909 Lacerta saxicola mixta LANTZ & CYREN, 1936 Darevskia mixta ARRIBAS, 1997 Darevskia mixta DORONIN, 2018 |
Méhely, L. (1909) - Description of Darevskia caucasica. – In: “Materialien zu einer Systematik und Phylogenie der muralis-ähnlichen Lacerten”. - Annales historico-naturales Musei nationalis Hungarici, Budapest, 7 (2): 409-621.  Uzzell, T. & Darevsky, I.S. (1975) - Biochemical evidence for the hybrid origin of the parthenogenetic species of Lacerta saxicola complex (Sauria, Lacertidae) with a discussion of some ecological and evolutionary implications. - Copeia, 1975 (2): 204-222.  × Five proteins (mannosephosphate isomerase, glucosephosphate isomerase, lactate dehydrogenase, creatine kinase, hemoglobin) were examined for six bisexual Transcaucasian taxa related to Lacerta saxicola (Lacerta valentini, L. portschinskii, L. raddei raddei, L. r. nairensis, L. mixta, L. parvula) and four unisexual taxa (Lacerta armeniaca, L. dahli, L. rostombekovi, L. unisexualis). Heterozygosity in the bisexual taxa was very limited for this sample of proteins. All individuals examined of each unisexual were heterozygous at loci specifying at least two of these proteins (L. armeniaca: mannosephosphate isomerase and creatine kinase; L. dahli, mannosephosphate isomerase and hemoglobin; L. rostombekovi, glucosephosphate isomerase, mannosephosphate isomerase and hemoglobin; L. unisexualis, glucosephosphate isomerase, mannosephosphate isomerase and creatine kinase). High levels of heterozygosity in unisexuals appears to result from the hybrid origin of the unisexuals. The exact combinations of alleles present in unisexuals would readily result from certain crosses among the bisexuals, and from no others. The first point supports the hypothesis that hybridization accounts for the observed heterozygosity, the second identifies, biochemically at least, the probable parents. On these biochemical grounds, L. armeniaca arose by hybridization of L. valentini and L. mixta; L. unisexualis from L. valentini and L. r. nairensis; L. rostombekovi from L. r. raddei and L. portschinskii; and L. dahli from L. portschinskii and L. mixta. With regard to altitudinal distribution, vegetational associations and geographic distribution, each unisexual species appears to be intermediate between its putative parental species. L. armeniaca, L. unisexualis and L. rostombekovi all live in drier situations than either parental species. L. dahli is an exception since it occupies slightly more moist habitats than L. portschinskii. Biogeographical considerations appear to place the age of L. unisexualis and L. rostombekovi at greater than 5000 years. It is possible that their occupancy of more extreme habitats than their parental species represents a relic ecology, reflecting the adaptations of the parental bisexual species when the unisexual species arose, rather than a weed habitat into which they moved to escape from competition with their parental species. The fixed heterozygosity of the unisexual species of Lacerta indicates that the restitution of somatic diploidy results either from a premeiotic endoduplication without cytokinesis, or from fusion of the female pronucleus with one of the second division meiotic products of the first polar nucleus. The first mechanism is inconsistent with the number of bivalents reported, the second is otherwise unknown in organisms in which the first polar nucleus becomes a polar body. The bisexual taxa are treated as several distinct species, four pairs of which are partly sympatric with little or no hybridization. Morphological and ecological differences between the other taxa are so great that there seems little question about specific distinctness. The degree of biochemical and morphological difference between these non-sympatric taxa is as great as that between those that do occur sympatrically without fusing. The formation of parthenogenetic species as a result of past hybridization between some pairs indicates a great selective disadvantage to these pairs of hybridizing, and is thus compelling evidence that the two members of each pair are not conspecific. Bischoff, W. (2003) - Die Eidechsenfauna Georgiens. Teil II. Die Gattung Darevskia. - Die Eidechse, Bonn, 14 (3): 65-93. × In Georgia, 16 species of rock lizards of the Genus Darevskia are occuring (D. alpina, D.
„armeniaca`, D. brauneri, D. caucasica, D. clarkorum, D. daghestanica, D. „dahli`, D.
derjugini, D. mixta, D. nairensis, D. parvula, D. portschinskii, D. praticola, D. rudis, D.
„unisexualis` and D. Valentini). Besides short presentations of the single species and hints on their distribution and habitats, also some systematic remarks are given. Gabelaia, M. & Tarkhnishvili, D. & Murtskhvaladze, M. (2015) - Phylogeography and morphological variation in a narrowly distributed Caucasian rock lizard, Darevskia mixta. - Amphibia-Reptilia, 36 (1): 45-54. × The Caucasian rock lizard Darevskia mixta was sampled and studied from throughout its range, using mitochondrial cytochrome b sequences and scalation. The populations of the Greater and the Lesser Caucasus are reciprocally monophyletic matrilineally, and the respective lineages have been separated since the mid-Pleistocene. The lizards from the Greater Caucasus commonly have an unpaired preanal scale, whereas the lizards from the Lesser Caucasus have an additional scale behind the central temporal and subdivided interparietal scale more commonly than those from the Greater Caucasus. The Lesser Caucasus populations are further subdivided into two geographically distinct matrilineages, and are more diverse genetically and morphologically than the Greater Caucasus populations. The central part of the Lesser Caucasus is suggested to be the ancestral area for the entire D. mixta lineage. Successive Pleistocene periods of glaciation appear to be responsible both for the isolation of D. mixta from its common relatives, and for subdivision within D. mixta. Presence of D. mixta in NE Turkey is challenged.
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