Anguidae
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Four species of legless anguid lizard genus Anguis have been currently recognized: A. fragilis from western and central Europe, A. colchica from eastern Europe and western Asia, A. graeca from southern Balkans, and A. cephallonica from the Peloponnese. Slow worms from the Italian Peninsula have been considered conspecific with A. fragilis, despite the fact that the region served as an important speciation center for European flora and fauna, and included some Pleistocene glacial refugia. We used mitochondrial and nuclear DNA sequences to investigate the systematic and phylogenetic position of the Italian slow-worm populations and morphological analyses to test for phenotypic differentiation from A. fragilis from other parts of Europe. Our phylogenetic analyses revealed that Italian slow worms form a distinct deeply differentiated mtDNA clade, which presumably diverged during or shortly after the basal radiation within the genus Anguis. In addition, the specimens assigned to this clade bear distinct haplotypes in nuclear PRLR gene and show morphological differentiation from A. fragilis. Based on the differentiation in all three independent markers, we propose to assign the Italian clade species level under the name Anguis veronensisPollini, 1818. The newly recognized species is distributed throughout the Italian Peninsula to the Southern Alps and south-eastern France. We hypothesize that the Tertiary Alpine orogeny with subsequent vicariance might have played a role in differentiation of this species. The current genetic variability was later presumably shaped in multiple glacial refugia within the Italian Peninsula, with the first splitting event separating populations from the region of the Dolomite Mountains.
- Klíčová slova
- Cryptic diversity, Miocene, Morphological differentiation, Phylogeny, Phylogeography, Southern refugia,
- MeSH
- Bayesova věta MeSH
- biologická evoluce * MeSH
- buněčné jádro genetika MeSH
- fylogeneze * MeSH
- genetická variace MeSH
- haplotypy MeSH
- ještěři anatomie a histologie klasifikace genetika MeSH
- mitochondriální DNA genetika MeSH
- pravděpodobnostní funkce MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Itálie MeSH
- Názvy látek
- mitochondriální DNA MeSH
Phylogenetic relationships of the Western Palearctic legless lizard genus Anguis were inferred based on a fragment of mitochondrial DNA and two nuclear protein-coding loci, C-mos and PRLR. A. cephallonica from the Peloponnese was confirmed as a valid species. It is the sister taxon to a clade comprising all other evolutionary lineages, which were shown to represent three distinct species: (1) A. fragilis sensu stricto occurring in Western and Central Europe, the north-western Balkans, with possibly isolated populations in the eastern Balkans, and presumably also in western Scandinavia and Italy; (2) A. colchica distributed from the eastern Czech Republic and the Baltic region eastward to northern Iran, presumably also in eastern Scandinavia, and the north-eastern Balkans; (3) A. graeca restricted to the southern Balkans, and partially sympatric with A. cephallonica. According to the more variable mitochondrial marker, A. graeca appears to be the sister species to A. colchica, and these taxa together form a sister clade to A. fragilis, whereas the less variable nuclear markers show A. colchica to be closer to A. fragilis. The C-mos gene has not provided substantial variation within this species complex, while the PRLR gene, which was used for the first time in phylogeographic study in a reptile, distinguished all species successfully. Intra-specific differentiation of A. colchica is discussed, and subspecific status of the Caucasian and Caspian populations is proposed. The uncovered genetic differences should be taken into account in all future biogeographical, morphological and ecological studies, as well as in conservation.
- MeSH
- buněčné jádro genetika MeSH
- fylogeneze * MeSH
- ještěři klasifikace genetika MeSH
- mitochondriální DNA genetika MeSH
- modely genetické MeSH
- molekulární evoluce * MeSH
- sekvenční analýza DNA MeSH
- sekvenční seřazení MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
- Názvy látek
- mitochondriální DNA MeSH
A dated phylogenetic hypothesis on the evolutionary history of the extant taxa of the Western Palearctic lizards Anguis and Pseudopus is revised using genome-wide nuclear DNA and mitogenomes. We found overall concordance between nuclear and mitochondrial DNA phylogenies, with one significant exception - the Apennine A. veronensis. In mitochondrial DNA, this species forms a common clade with the earliest diverging lineage, the southern Balkan endemic A. cephallonica, while it clusters together with A. fragilis in nuclear DNA. The nuclear phylogeny conforms to the morphology, which is relatively similar between A. veronensis and A. fragilis. The most plausible explanation for the mitonuclear discordance is ancient mitochondrial capture from the Balkan ancestor of A. cephallonica to the Apennine population of the A. fragilis-veronensis ancestor. We hypothesize that this capture occurred only in a geographically restricted population. The dating of this presumed mitochondrial introgression and capture coincides with the Messinian event, when the Balkan and Apennine Peninsulas were presumably largely connected. The dated nuclear phylogenomic reconstruction estimated the divergence of A. cephallonica around 12 Mya, while the sister clade representing the A. fragilis species complex consisting of the sister species A. fragilis-A. veronensis and A. colchica-A. graeca further diversified around 7 Mya. The depth of nuclear divergence among the evolutionary lineages of Pseudopus (0.5-1.2 Mya) supports their subspecies status.
- Klíčová slova
- Evolutionary history, Glass lizard, Introgression, Messinian salinity crisis, Mitonuclear discordance, Slow worm,
- MeSH
- biologická evoluce * MeSH
- fylogeneze MeSH
- ještěři * MeSH
- mitochondriální DNA genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Balkánský poloostrov MeSH
- Názvy látek
- mitochondriální DNA MeSH
BACKGROUND: Legless lizards, the slow worms of the genus Anguis, are forming secondary contact zones within their Europe-wide distribution. METHODS: We examined 35 populations of A. fragilis and A. colchica to identify the level of morphological and genetic divergence in Poland. We applied a conventional study approach using metric, meristic, and categorial (coloration) features for a phenotype analysis, and two standard molecular markers, a mitochondrial (NADH-ubiquinone oxidoreductase chain 2; ND2) and a nuclear (V(D)J recombination-activating protein 1; RAG1) one. RESULTS: We found clear differences between A. fragilis and A. colchica in molecular markers and phenotype-in meristic features, e.g., ear opening, number of scales rows around the body, and higher than so far known diversity in ND2 and RAG1 haplotypes. The presence of five hybrids was detected in three populations in the Polish part of the European contact zone. In all hybrids, homozygous alleles of RAG1 were detected, which suggests a back-crossing within the genus. CONCLUSIONS: The ability to produce fertile offspring by A. fragilis x A. colchica hybrids shows inefficient mechanisms of reproductive isolation of the two legless lizards. The hybrids were indistinguishable from parental species in head proportions (principal components and discriminant analyses) but more resembling A. colchica in meristic traits.
- Klíčová slova
- Anguidae, Biogeography, Hybridization, Morphometrics, Speciation, Taxonomy,
- MeSH
- fenotyp MeSH
- genetická variace MeSH
- haplotypy genetika MeSH
- ještěři * genetika anatomie a histologie MeSH
- reprodukční izolace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Polsko MeSH
- Názvy látek
- homeodoménové proteiny MeSH
- RAG-1 protein MeSH Prohlížeč
BACKGROUND: Genetic architecture of a species is a result of historical changes in population size and extent of distribution related to climatic and environmental factors and contemporary processes of dispersal and gene flow. Population-size and range contractions, expansions and shifts have a substantial effect on genetic diversity and intraspecific divergence, which is further shaped by gene-flow limiting barriers. The Balkans, as one of the most important sources of European biodiversity, is a region where many temperate species persisted during the Pleistocene glaciations and where high topographic heterogeneity offers suitable conditions for local adaptations of populations. In this study, we investigated the phylogeographical patterns and demographic histories of four species of semifossorial slow-worm lizards (genus Anguis) present in the Balkan Peninsula, and tested the relationship between genetic diversity and topographic heterogeneity of the inhabited ranges. RESULTS: We inferred phylogenetic relationships, compared genetic structure and historical demography of slow worms using nucleotide sequence variation of mitochondrial DNA. Four Anguis species with mostly parapatric distributions occur in the Balkan Peninsula. They show different levels of genetic diversity. A signature of population growth was detected in all four species but with various courses in particular populations. We found a strong correlation between genetic diversity of slow-worm populations and topographic ruggedness of the ranges (mountain systems) they inhabit. Areas with more rugged terrain harbour higher genetic diversity. CONCLUSIONS: Phylogeographical pattern of the genus Anguis in the Balkans is concordant with the refugia-within-refugia model previously proposed for both several other taxa in the region and other main European Peninsulas. While slow-worm populations from the southern refugia mostly have restricted distributions and have not dispersed much from their refugial areas, populations from the extra-Mediterranean refugia in northern parts of the Balkans have colonized vast areas of eastern, central, and western Europe. Besides climatic historical events, the heterogeneous topography of the Balkans has also played an important role in shaping genetic diversity of slow worms.
- Klíčová slova
- Anguidae, Balkan mountains, Biogeography, Contact zones, Microrefugia, Phylogeography, Speciation, Squamata,
- MeSH
- biodiverzita MeSH
- fylogeneze MeSH
- fylogeografie MeSH
- ještěři genetika MeSH
- mitochondriální DNA genetika MeSH
- molekulární evoluce MeSH
- polymorfismus genetický MeSH
- tok genů MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Balkánský poloostrov MeSH
- Názvy látek
- mitochondriální DNA MeSH
We present a comprehensive summary of the distribution of the lizards of Iran accompanied by an annotated checklist. The updated maps of distribution of all 146 species of 41 genera of 11 families are based on all available bibliographic records, catalogues of museum collections and our own field observations. The final dataset used for the distribution maps contains 8525 georeferenced records and cover 41% of the country when plotted on a grid of 0.25° × 0.25° resolution. The dataset is publicly accessible through GBIF portal (http://www.gbif.org/dataset/7db4f705-61ae-4c6e-9de2-06674e7d46b2). Following the latest biogeographic division of the country, ~53% of the species (76 species) inhabit the Iranian Province, ~41% (60 species) the Western Asian mountain transition zone, ~9% (13 species) the Turanian Province, and ~18% (27 species) the Arabian Province. In addition, ~2% (3 species) reach Iran from the Indo-Malay biogeographic region and ~2% (3 species) are believed to have been introduced to Iran by humans. Endemic species (46) represent ~32% of the known species diversity. The most species-rich family of lizards in Iran is Lacertidae with 47 species, followed by Gekkonidae (41), Agamidae (18), Scincidae (15), Phyllodactylidae (10), Sphaerodactylidae (4), Eublepharidae and Uromastycidae (3), Anguidae and Varanidae (2), and Trogonophidae with one representative.
- MeSH
- anatomické struktury zvířat anatomie a histologie růst a vývoj MeSH
- ještěři anatomie a histologie klasifikace růst a vývoj MeSH
- kontrolní seznam MeSH
- rozšíření zvířat MeSH
- velikost orgánu MeSH
- velikost těla MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Írán MeSH
Anguimorphan lizards are a morphologically variable group of squamate reptiles with a wide geographical distribution. In spite of their importance, they have been cytogenetically understudied. Here, we present the results of the cytogenetic examination of 23 species from five anguimorphan families (Anguidae, Helodermatidae, Shinisauridae, Varanidae and Xenosauridae). We applied both conventional (Giemsa staining and C-banding) and molecular cytogenetic methods (fluorescence in situ hybridization with probes for the telomeric motifs and rDNA loci, comparative genome hybridization), intending to describe the karyotypes of previously unstudied species, to uncover the sex determination mode, and to reveal the distribution of variability in cytogenetic characteristics among anguimorphan lizards. We documented that karyotypes are generally quite variable across anguimorphan lineages, with anguids being the most varying. However, the derived chromosome number of 2n = 40 exhibits a notable long-term evolutionary stasis in monitors. Differentiated ZZ/ZW sex chromosomes were documented in monitors and helodermatids, as well as in the anguids Abronia lythrochila, and preliminary also in Celestus warreni and Gerrhonotus liocephalus. Several other anguimorphan species have likely poorly differentiated sex chromosomes, which cannot be detected by the applied cytogenetic methods, although the presence of environmental sex determination cannot be excluded. In addition, we uncovered a rare case of spontaneous triploidy in a fully grown Varanus primordius.
- Klíčová slova
- CGH, FISH, evolution, karyotype, rDNA, sex chromosomes, telomeres,
- MeSH
- cytogenetické vyšetření * MeSH
- fylogeneze MeSH
- ještěři genetika MeSH
- karyotyp * MeSH
- metafáze genetika MeSH
- molekulární evoluce * MeSH
- pohlavní chromozomy genetika MeSH
- ribozomální DNA genetika MeSH
- telomery genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- ribozomální DNA MeSH
BACKGROUND: The application of molecular-phylogenetic approaches to taxonomy has had a dramatic effect on our understanding of the diversity of reptiles. These approaches have allowed researchers to reveal previously hidden lineages as well as taxonomic overestimation in morphologically plastic taxa. Slow worms, legless lizards of the genus Anguis (Squamata: Anguidae), were previously considered to comprise either one or two species, and morphology-based intraspecific taxonomy of Anguis fragilis remained controversial throughout the 20th century. After the discovery of deep genetic divergences within the genus, its taxonomy was reconsidered, and as a result, five extant species have been recognized. In order to better understand the patterns of their interspecific differentiation, here we studied phenotypic differences between the two most widespread of them-A. fragilis and A. colchica, and their putative hybrids across the contact zone of both species in Central Europe. METHODS: We used multivariate and univariate statistics and analyzed ten metric, eleven meristic, and six categorical phenotypic variables in material comprising a total of 326 individuals. We also genotyped individuals from the contact zone for one mitochondrial and two nuclear DNA fragments in order to delineate the distribution of individuals of hybrid and non-hybrid origin. The clines in morphological traits were studied using HZAR. RESULTS: We show that the two species are morphologically differentiated. Anguis fragilis has a less robust head, fewer scales covering the body, lower frequency of the external ear opening presence, lower frequency of separated prefrontal scales, higher frequency of prefrontal scales in contact with each other, and body coloration more similar to the juvenile coloration than A. colchica. Slow worms from the contact/hybrid zone are characterized by an intermediate morphology, with more similarities to A. fragilis than to A. colchica. DISCUSSION: None of the analyzed characters alone proved to be fully diagnostic, although more than 90% of all individuals could be successfully assigned to one or another species based on numbers of scales around the body. Our results indicate concordant, coincident, and steep clines in character states change. We present several hypotheses on the origin and evolutionary maintenance of the morphological divergence between both species and suggest that different evolutionary histories of the taxa rather than recently acting selection explain the observed morphological variation.
- Klíčová slova
- Coloration, Diversity, Hybrid zone, Hybridization, Lizards, Morphology, Morphometrics, Reptilia, Sauria, Western Palearctic,
- Publikační typ
- časopisecké články MeSH