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Lacertid and amphisbaenian lizards are two squamate reptile lineages very divergent morphologically. In fact, adaptation to burrowing deeply modified amphisbaenian worm-like body. Lacertids instead have a typical reptile morphology with a long tail and four well-developed limbs. Despite so different in appearance, they are evolutionarily very close as evidenced by molecular phylogenetic approaches. Consistently, a slow-evolving satellite DNA (IMO-TaqI) described in lacertid lizards was isolated from the genome of the amphisbaenian Trogonophis wiegmanni too. Comparison with lacertid repeats evidenced great similarity, highlighting that molecular characters appeared very suitable especially when morphology is subjected to strong selective pressures. [ABSTRACT FROM AUTHOR]

Lacertid and amphisbaenian lizards are two squamate reptile lineages very divergent morphologically. In fact, adaptation to burrowing deeply modified amphisbaenian worm-like body. Lacertids instead have a typical reptile morphology with a long tail and four well-developed limbs. Despite so different in appearance, they are evolutionarily very close as evidenced by molecular phylogenetic approaches. Consistently, a slow-evolving satellite DNA (IMO-TaqI) described in lacertid lizards was isolated from the genome of the amphisbaenian Trogonophis wiegmanni too. Comparison with lacertid repeats evidenced great similarity, highlighting that molecular characters appeared very suitable especially when morphology is subjected to strong selective pressures.

Although the effects of global warming on thermoregulation are usually explored using predictions of climate envelop modelling, such effects should best be analysed empirically, studying the same population with the same methods after a long enough period of temperature rise.We used a 30‐year long database about body temperatures (Tbs) of field‐active Psammodromus algirus lizards inhabiting a well‐conserved temperate open forest, and we focused on the summers of 1997 and 2017 to compare Tbs, environmental operative temperatures (Tes), their proximity to the selected thermal range (Tsel), and the selection of sunlit and shaded patches all along the day. From these data, we estimated the precision (standard deviation of Tbs), accuracy (average distance between Tbs and Tsel) and effectiveness (extent to which Tbs are closer to Tsel than Tes) of thermoregulation.Of the highest 5% of all Tbs in the database, 95% were recorded in 2017, when the adjustment to Tsel was much better for Tbs selected in a laboratory thermogradient than for field Tbs (percentages of Tbs above Tsel of 2% and 52% respectively).In 2017, especially after 12:00 h, the selection of shaded patches (87% of lizards in full shade vs. <1% in full sun) was more intense than in 1997, contributed more to overall thermoregulation, and produced a larger difference between Tes and Tbs. In spite of this, Tbs were lower—and closer to Tsel—in 1997 (when most shaded patches offered favourable thermal opportunities, with Tes within or below Tsel) than in 2017 (when only 33% of full shade Tes, and 8% of all Tes, were within or below Tsel). As a consequence, estimates of the accuracy and effectiveness of thermoregulation decreased over the 20‐year period examined.We conclude that given the low availability of Tes within or below Tsel, lizards cannot longer prevent the rise of their Tbs above Tsel, at least in hot summer days. Thus, the effects of global warming are already hindering the ability of lizards to buffer environmental change by behavioural means, even in temperate forests with a fine‐grained mosaic of sun and shade patches. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

We analysed the effects of body mass on the monthly activity patterns of six Mediterranean lacertid lizard taxa, four relatively small species, the Italian wall lizard (Podarcis siculus), the common wall lizard (Podarcis muralis), the blue-throated keeled lizard (Algyroides nigropunctatus), and the Ionian wall lizard (Podarcis ionicus), and two larger species, the western green lizard (Lacerta bilineata) and the Balkan green lizard (Lacerta trilineata). The highest number of observations for all six species occurred in April and May and the lowest in July and August, the latter being the hottest and driest months of the year. The two larger species were mainly active from March to July, whereas the four smaller species had an additional period of high activity from September to November. As all six species reproduce during spring, the increase in activity of the smaller species in autumn was consequently unrelated to reproductive behaviour. There was no difference in seasonal activity of the two smaller Italian species at sites with or without the larger green lizards. It is therefore unlikely that interference competition/predation by green lizards caused the increased autumnal activity of the smaller lizards. We suggest that due to their lower mass-specific metabolic rates, larger species can obtain sufficient lipid stores over a shorter annual activity to ensure successful reproduction the subsequent spring. By contrast, smaller species have greater need to replenish their lipid reserves after summer fasting and therefore resume much higher activity levels in September to November to attain this goal. [ABSTRACT FROM AUTHOR]

Timon, a small genus of lacertid lizards, includes four species distributed in two separate ranges in the western and eastern part of the Mediterranean Basin. Phylogenetic relationships between the two groups have not been resolved, and the taxonomic situation of the two subspecies of the eastern representative of the genus, Timon princeps, is not clear. To address these questions, partial DNA sequences of two nuclear (ß-fibrinogen intron 7 and C-mos) and three mitochondrial (cytochrome b, 12S rRNA and 16S rRNA) genes were analyzed. Based on the high genetic distance between the two subspecies of T. princeps we promote their taxonomic status to full species, Timon princeps and Timon kurdistanicus. Divergence time estimates based on other lacertid species suggest that the separation of the green (Lacerta) and ocellated (Timon) lizards took place around 12 My ago, and that the Eastern group underwent speciation around 4-5 my ago, perhaps associated with the uplifting of the Zagros mountains. As expected given this ancient divergence and complex paleogeography, considerable levels of genetic diversity are recovered within both taxa, with geographically close individuals showing very divergent haplotypes. [ABSTRACT FROM AUTHOR]

Aim We explored the phylogenetic relationships of species of Mesalina, using one nuclear and two mitochondrial loci. This genus of lacertid lizards is widely distributed in North Africa and the Middle East and our goal was to develop a scenario capable of explaining the current distribution and evolutionary patterns within the genus in the context of the wider historical biogeography of the region. Location North Africa and the Middle East. Methods The assembled dataset consisted of 193 Mesalina individuals, representing 12 species distributed across the geographical range of the genus. Bayesian and maximum likelihood methods were used to support phylogenetic inferences on two mitochondrial (cytochrome b and 16S ribosomal RNA) and one nuclear (beta-fibrinogen intron 7) markers. Palaeogeographical and palaeoclimatic data were used to support the inferred phylogeographical patterns. Results Mesalina lizards exhibit high genetic diversity and complex phylogenetic patterns, leading to an unsatisfactory systematic hypothesis of one paraphyletic and three polyphyletic traditional species. The estimated divergence times place the origin of the genus in the early Miocene ( c. 22 Ma) and the divergence of most currently recognized species in the middle to late Miocene. The inferred ancestral distribution suggests that the genus and most of its species originated somewhere in Arabia or the Middle East, with the exception of the Mesalina olivieri complex, which may be of African origin. Main conclusions Phylogenetic reconstruction based on the three loci studied suggests a higher than expected cryptic diversity of Mesalina in North Africa and the Middle East. We suggest that the tectonic movements of the Arabian plate, coupled with the climatic changes occurring since the Miocene, may be responsible for the phylogeographical patterns of North African and Middle Eastern Mesalina. [ABSTRACT FROM AUTHOR]

We analysed patterns of skull size and shape variation among populations of the Common wall lizard (Podarcis muralis) in the Central Balkans, particularly the effecs of insularity and the presence of the ecologically similar lacertid lizard species P. melisellensis. Two components of shape variation were analysed - size dependent (allometric) and size independent shape changes. The observed shape differentiation relating to insularity was greatly size-dependent and concordant to allometric shape changes which explained over 20% of variation in the skull shape in the analysed sample. The explorative analysis of size-independent shape changes revealed that populations of P. muralis which share habitat with P. melisellensis diverge from populations which do not share habitat with potentially competing species. These changes related to the general shortening and widening of the skull and increase of the jaw adductor muscle chambers were more pronounced in males. We suppose that the observed pattern of shape changes is driven by competition among species (character displacement) and, possibly, is further modified by heterospecific aggression and trophic shift. [ABSTRACT FROM AUTHOR]

Aim Diversification and rapid radiation are well documented in lacertid lizards. Niche conservation is frequently observed among related taxa, whereby niches will not change much during speciation events. Here, we investigate the relationship between environmental niche divergence and phylogenetic relatedness in a widespread group of green lizards, the Lacerta trilineata group. Location Eastern Mediterranean, Anatolia and adjacent regions. Methods A dated phylogeny based on three mitochondrial genes was contextualized using species distribution models of all genetically identified lineages in the Lacerta trilineata group. Based on this analysis, ancestral climatic niche occupancy was reconstructed using niche occupancy profiles. Niche divergence among lineages was quantified by computing multivariate niche overlaps. Results All taxa are associated with humid areas, but there is extensive variation in their climatic niche breadths and positions, which accord with the main phylogenetic split in the group. Our results suggest divergent niche evolution within subclades and convergent evolution among clades, which implies only a limited degree of niche conservatism regarding annual variations in temperature and precipitation. In contrast, niche axes - mainly reflecting precipitation patterns of the coldest quarter - show a greater difference among clades than within clades, and therefore a higher degree of niche conservatism. Main conclusions Based on estimated divergence times between taxa and geological events in Anatolia, our results can be explained by fragmentation of the range of a hypothetical ancestral species, resulting in different adaptations of subclades either to humid continental climates or to more Mediterranean climates. Our study highlights deviations from classical niche conservatism theory due to significant niche shifts among sister taxa. [ABSTRACT FROM AUTHOR]

Abstract: We used geometric morphometrics to explore the influence of phylogenetic and allometric constraints as well as ecology on variation in cranium shape in five species of monophyletic, morphologically similar Podarcis lizards (Podarcis erhardii, Podarcis melisellensis, Podarcis muralis, Podarcis sicula and Podarcis taurica). These species belong to different clades, they differ in their habitat preferences and can be classified into two distinct morphotypes: saxicolous and terrestrial. We found (i) no phylogenetic signal in cranium shape, (ii) diverging allometric slopes among species, and (iii) a significant effect of habitat on cranium shape. The saxicolous species (P. erhardii and P. muralis) had crania with elongated parietals, elongated cranium bases, shortened anterior parts of the dorsal cranium, reduced chambers of the jaw adductor muscles and larger subocular foramina. These cranial features are adaptations that compensate for a flattened cranium, dwelling on vertical surfaces and seeking refuge in crevices. The crania of the terrestrial species (P. melisellensis, P. sicula and P. taurica) tended to be more elongate and robust, with enlarged chambers of the jaw adductor muscle, reduced skull bases and shortened parietals. Terrestrial species exhibited more variation in cranium shape than saxicolous species. Our study suggests that shape variation in Podarcis sp. lizards is largely influenced by ecology, which likely affects species-specific patterns of static allometry. [Copyright &y& Elsevier]

Timon, a small genus of lacertid lizards, includes four species distributed in two separate ranges in the western and eastern part of the Mediterranean Basin. Phylogenetic relationships between the two groups have not been resolved, and the taxonomic situation of the two subspecies of the eastern representative of the genus, Timon princeps, is not clear. To address these questions, partial DNA sequences of two nuclear (β-fibrinogen intron 7 and C-mos) and three mitochondrial (cytochrome b, 12S rRNA and 16S rRNA) genes were analyzed. Based on the high genetic distance between the two subspecies of T. princeps we promote their taxonomic status to full species, Timon princeps and Timon kurdistanicus. Divergence time estimates based on other lacertid species suggest that the separation of the green (Lacerta) and ocellated (Timon) lizards took place around 12 My ago, and that the Eastern group underwent speciation around 4-5 my ago, perhaps associated with the uplifting of the Zagros mountains. As expected given this ancient divergence and complex paleogeography, considerable levels of genetic diversity are recovered within both taxa, with geographically close individuals showing very divergent haplotypes. [ABSTRACT FROM AUTHOR]

Relationships among Psammodromus algirus populations from the Iberian Peninsula and North Africa, including recently described P. jeanneae and P. manuelae, were estimated from mitochondrial DNA gene sequences. This enlarged data set confirmed the presence of two divergent eastern and western mitochondrial DNA lineages on the Iberian Peninsula, the distributions for which are separated by a narrow zone of contact across the centre of the Peninsula. Paratypes of P. jeanneae and topotypes of P. manuelae represent southern and northern clades of the western lineage, respectively, making P. algirus paraphyletic. This, together with the low level of allozymic and mitochondrial DNA substructuring within western populations, is not sufficient to retain P. jeanneae and P. manuelae as valid species, and we relegate them to the status of junior synonyms of P. algirus. [ABSTRACT FROM AUTHOR]

The Persian racerunner Eremias persica Blanford, 1875 is confined to the Iranian plateau, and forms one of the most widespread but rarely studied species of the family Lacertidae. With many local populations inhabiting a variety of habitats, and exhibiting considerable morphological, genetic, and ecological variations, it represents a species complex. We analysed sequences of mitochondrial cytochrome b and 12S ribosomal RNA (rRNA) genes derived from 13 geographically distant populations belonging to the E. persica complex. Using our knowledge of palaeogeographical events, a molecular clock was calibrated to assess the major events in fragmentation, radiation, and intraspecific variation. The sequence data strongly support a basal separation of the highland populations of western Iran from those of the open steppes and deserts, occurring in the east. The subsequent radiation, fragmentation, and evolution of these major assemblages have led to several discernable geographical lineages across the wide area of the Iranian plateau. The results indicate a middle-Miocene origin for the clade as a whole. The first split, isolating the western and eastern clades, appears to have occurred 11–10 Mya. Further fragmentations and divergence within the major clades began about 8 Mya, with an evolutionary rate of 1.6% sequence divergence per million years among the lineages in the genes studied (combined data set). Molecular and morphological data strongly support a taxonomic revision of this species complex. At least four of the discovered clades should be raised to species, and two to subspecies, rank. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158, 641–660. [ABSTRACT FROM AUTHOR]

Natural vegetation in Europe appears nowadays deeply modified by human activities. In the Guadarrama Mountains (Central Spain), ancient reforestations with Scots pines, Pinus sylvestris, replaced original deciduous pyrenean oak, Quercus pyrenaica, forests (since the Roman period). However, the effect of reforestations on fauna remains little known, especially in reptiles. We described patterns of microhabitat selection in several species of Lacertid lizards, and analyzed whether the modification of the original vegetation affected distribution and population densities of lizards. The species of lacertid lizards found in oak forests (Psammodromus algirus, Lacerta lepida and Podarcis hispanica) were different to those of in pine plantations (Podarcis muralis and Podarcis hispanica). Lizards did not use habitat at random and this could explain differences in species found in both forests, which differed in some microhabitat structure characteristics. Most lizards selected microhabitats with rocky outcrops, with low cover of trees, and close to refuges. These microhabitat preferences also explained abundance of lizards in transects. From the perspective of conservation and management of lizards, pine plantations seem not to contribute too much to the diversity of lizard species because species typical from oak forests were lost. This study has implications for pine reforestation management, because allowing the recolonization by understory oaks, and leaving some open areas, without trees but with dense shrubs and rocks inside reforestations would contributed to maintain lizard populations. [ABSTRACT FROM AUTHOR]

Karyological (standard and C, Ag-NOR and Alu-I banding methods) and mtDNA analyses (cytochrome b and 12S rRNA) were conducted on specimens from eight allopatric populations of the Lacerta kulzeri complex. Parallel analyses were performed for comparison on Lacerta laevis specimens. Karyological and molecular studies support the morphological and ethological evidence indicating the specific separation between Lacerta laevis and Lacerta kulzeri In the Lacerta kulzeri complex, chromosomal analysis substantiated an interpopulation differentiation roughly along a north–south trend, mainly regarding the sex chromosome morphology and heterochromatin.The cytochrome b and 12S rRNA gene analyses showed minor genetic differences that were considerably smaller than those commonly found in genetically isolated populations. The L. kulzeri populations from Barouk, Druze and Hermon show a mean genetic distance that, in other saurians, characterises subspecies. The conditions found in L. laevis and L. kulzeri are reminiscent of King's model of chromosomal primary allopatry and support the hypothesis that in these lacertid lizards chromosome variations can become fixed before the accumulation of the genetic mutations. [ABSTRACT FROM AUTHOR]

Management of dehesas (i.e. oak woodland pastures) creates a patchwork of sectors that differ in their structure and composition of understorey vegetation. We analysed whether different management techniques affect the populations of several species of lizards (Podarcis hispanica, Psammodromus algirus, Psammodromus hispanicus, Acanthodactylus erythrurus, and Lacerta lepida). Multivariate analyses showed that lizards preferentially used forested areas with scrub while they avoided open herbaceous areas. The abundance of lizards increased when the understorey bushy vegetation increased. In contrast, grasslands or cereal fields were scarcely occupied even if holm oak trees (Quercus ilex) were present, apparently because low shrubs were scarce here. Therefore, some of the traditional management practices of dehesas may negatively affect lizard populations. These conclusions could have wider implications for the design of wildlife reserves within dehesas, which has been previously based on the umbrella species concept (e.g. some dehesas are managed for imperial eagle Aquila adalberti conservation), without considering habitat requirements of other representative animal groups. [Copyright &y& Elsevier]

The chromosome C-banding pattern has been studied in four lacertid species possessing the same karyotype. The results obtained show a remarkable interspecific variability both in the amount and distribution of C-banded heterochromatin. This leads us to the speculation that alleged conservativeness in their karyology is probably due to inadequate resolution by the conventional cytological techniques. Moreover, it has been hypothesized that these variations of the C-bands play an important role in the evolution of this saurian family. [ABSTRACT FROM AUTHOR]