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1.
Animals (Basel) ; 14(7)2024 Apr 07.
Article En | MEDLINE | ID: mdl-38612363

The Mongolian racerunner, Eremias argus, is a small lizard endemic to Northeast Asia that can serve as an excellent model for investigating how geography and past climate change have jointly influenced the evolution of biodiversity in this region. To elucidate the processes underlying its diversification and demography, we reconstructed the range-wide phylogeographic pattern and evolutionary trajectory, using phylogenetic, population genetic, landscape genetic, Bayesian phylogeographic reconstruction and ecological niche modeling approaches. Phylogenetic analyses of the mtDNA cyt b gene revealed eight lineages that were unbounded by geographic region. The genetic structure of E. argus was mainly determined by geographic distance. Divergence dating indicated that E. argus and E. brenchleyi diverged during the Mid-Pliocene Warm Period. E. argus was estimated to have coalesced at~0.4351 Ma (Marine Isotope Stage 19). Bayesian phylogeographic diffusion analysis revealed out-of-Inner Mongolia and rapid colonization events from the end of the Last Interglacial to the Last Glacial Maximum, which is consistent with the expanded suitable range of the Last Glacial Maximum. Pre-Last Glacial Maximum growth of population is presented for most lineages of E. argus. The Glacial Maximum contraction model and the previous multiple glacial refugia hypotheses are rejected. This may be due to an increase in the amount of climatically favorable habitats in Northeast Asia. Furthermore, E. argus barbouri most likely represents an invalid taxon. The present study is the first to report a range-wide phylogeography of reptiles over such a large region in Northeast Asia. Our results make a significant contribution towards understanding the biogeography of the entire Northeast Asia.

3.
J Dev Biol ; 11(2)2023 May 24.
Article En | MEDLINE | ID: mdl-37367476

Osteoderms are bony structures that develop within the dermal layer of the skin in vertebrates and are very often found in different lizard families. Lizard osteoderms are diverse in topography, morphology, and microstructure. Of particular interest are the compound osteoderms of skinks, which are a complex of several bone elements known as osteodermites. We present new data on the development and regeneration of compound osteoderms based on the results of a histological and Computed Microtomography (micro-CT) study of a scincid lizard: Eurylepis taeniolata. The specimens studied are stored in the herpetological collections of the Saint-Petersburg State University and Zoological Institute of the Russian Academy of Sciences located in St. Petersburg, Russia. The topography of osteoderms in the integuments of the original tail area and its regenerated part was studied. A comparative histological description of the original and regenerated osteoderms of Eurylepis taeniolata is presented for the first time. The first description of the development of compound osteoderm microstructure in the process of caudal regeneration is also presented.

4.
Zookeys ; 1148: 167-207, 2023.
Article En | MEDLINE | ID: mdl-37235140

Four new species of Diploderma are described from Sichuan and Yunnan provinces, southwestern China, based on an integrative taxonomic approach, combining morphological and genetic data. The first new species from Danba County, Sichuan Province, is morphologically most similar and phylogenetically closely related to D.flaviceps, but it can be diagnosed from the latter by having a relatively much shorter tail and by a genetic distance of 4.4% in the ND2 gene; the second new species from Muli County, Sichuan Province, is phylogenetically closely related to D.daochengense, D.yongshengense, and D.yulongense, but it can be diagnosed from the latter three species by having a pale yellow gular spot and by genetic distances of 5.6-6.7% in the ND2 gene; the third new species from Jiulong County, Sichuan Province, is morphologically most similar and phylogenetically closely related to D.angustelinea, but it can be diagnosed from the latter by having a relatively much longer tail and by a genetic distance of 2.8% in the ND2 gene; and the last new species from Weixi County, Yunnan Province, is phylogenetically closely related to D.aorun, but it can be diagnosed from the latter by having a pale yellow gular spot and by a genetic distance of 2.9% in the ND2 gene. Our work brings the number of species within the genus Diploderma to 46.

5.
Genes (Basel) ; 13(6)2022 05 25.
Article En | MEDLINE | ID: mdl-35741703

The Kokshaal racerunner, Eremias kokshaaliensis Eremchenko et Panfilov, 1999, together with other central Asian racerunner species, is included in the Eremias multiocellata complex. In the present work, for the first time, the results of the analysis of historical mitochondrial DNA (barcode) are presented and the taxonomic status and preliminary phylogenetic relationships within the complex are specified. We present, for the first time, the results of the molecular analysis using historical DNA recovered from specimens of several species of this complex (paratypes of the Kokshaal racerunner and historical collections of the Kashgar racerunner E. buechneri from Kashgaria) using DNA barcoding.


Lizards , Animals , DNA, Mitochondrial/genetics , Lizards/genetics , Mitochondria/genetics , Phylogeny , Sequence Analysis, DNA
6.
Nature ; 605(7909): 285-290, 2022 05.
Article En | MEDLINE | ID: mdl-35477765

Comprehensive assessments of species' extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4-7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened-confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods-agriculture, logging, urban development and invasive species-although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles-including most species of crocodiles and turtles-require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles.


Conservation of Natural Resources , Extinction, Biological , Reptiles , Alligators and Crocodiles , Amphibians , Animals , Biodiversity , Birds , Mammals , Phylogeny , Reptiles/classification , Risk Assessment , Turtles
7.
Zookeys ; 1131: 1-30, 2022.
Article En | MEDLINE | ID: mdl-36761463

Three new species of Diploderma are described from the Hengduan Mountain Region in south-western China, based on morphological and genetic data. The first new species from Yulong County, Yunnan Province is morphologically most similar and phylogenetically closely related to D.brevicauda, but it can be diagnosed from the latter by having a relatively longer tail; the second new species from Xiangcheng County, Sichuan Province is phylogenetically closely related to D.bowoense, but it can be diagnosed from the latter by the absence of a distinct gular spot; and the third new species from Yongsheng County, Yunnan Province is phylogenetically closely related to D.yulongense, but it can be diagnosed from the latter by having different colourations of the ventral and ventrolateral surfaces of the body. Taxonomy and diversity survey are the basis of species conservation, our discoveries contributing to better conservation of the species of this genus.

8.
Zookeys ; 1048: 79-89, 2021.
Article En | MEDLINE | ID: mdl-34305420

Based on the combination of molecular and morphological data, we herein report the second known finding of the xenodermid snake species Parafimbrios vietnamensis Ziegler, Ngo, Pham, Nguyen, Le & Nguyen, 2018. The male individual was found in the Yen Bai Province of northwestern Vietnam, more than 200 km from the type locality in Lai Chau Province. Genetic divergence between the newly-collected male and the holotype was low (1.7%), and is in agreement with morphological data that supports that they are conspecific. We give a detailed description of the morphological characters and coloration of the new record and provide an expanded diagnosis of P. vietnamensis. Parafimbrios is a poorly-understood genus, and our recent discovery brings the total number of known specimens of the genus to nine, 1/3 of them having been found in Vietnam (one specimen of P. lao and now two specimens of P. vietnamensis).

9.
Zootaxa ; 4722(2): zootaxa.4722.2.1, 2020 Jan 13.
Article En | MEDLINE | ID: mdl-32230629

A complete catalogue is provided for the type specimens of amphibians and reptiles collected by Nikolay A. Zarudny and stored mostly in the herpetological collection of the Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia (ZISP), as of August 2018. The collection contains 270 type specimens, representing 51 taxa (species and/or subspecies) of one family of turtles, one amphisbaenia family, five lizard families and four snake families from 74 type localities. As a result of studying Zarudny's collections, mainly from Iran, was the description by A. M. Nikolsky of two new genera, Microgecko and Diplometopon, and 42 species and subspecies (varieties). Twenty-two of these taxa are regarded currently as valid.


Lizards , Reptiles , Amphibians , Animals , Asia , Iran
10.
Zootaxa ; 4467(1): 1-81, 2018 Sep 03.
Article En | MEDLINE | ID: mdl-30313432

Phylogenetic relationships of the agamid lizard genus Phrynocephalus are described in the context of plate tectonics. A near comprehensive taxon sampling reports three data sets: (1) mitochondrial DNA from ND1 to COI (3' end of ND1, tRNAGln, tRNAIle, tRNAMet, ND2, tRNATrp, tRNAAla, tRNAAsn, tRNACys, tRNATyr, and the 5' end of COI) with 1761 aligned positional sites (1595 included, 839 informative), (2) nuclear RAG-1 DNA with 2760 aligned positional sites (342 informative), and (3) 25 informative allozyme loci with 213 alleles (107 informative when coded as presence/absence). It is hypothesized that Phrynocephalus phyletic patterns and speciation reflect fault lines of ancient plates now in Asia rejuvenated by the more recent Indian and Arabian plate collisions. Molecular estimates of lineage splits are highly congruent with geologic dates from the literature.  A southern origin for the genus in Southwest Asia is resolved in phylogenetic estimates and a northern origin is statistically rejected. On the basis of monophyly and molecular evidence several taxa previously recognized as subspecies are recognized as species: P. hongyuanensis, P. sogdianus, and P. strauchi as "Current Status"; Phrynocephalus bannikovi, Phrynocephalus longicaudatus, Phrynocephalus turcomanus, and Phrynocephalus vindumi are formally "New Status". Phylogenetic evaluation indicates a soft substrate habitat of sand for the shared ancestor of modern Phrynocephalus. Size diversity maximally overlaps in the Caspian Basin and northwestern Iranian Plateau. The greatest species numbers of six in sympatry and regional allopatry are found in the southern Caspian Basin and southern Helmand Basin, both from numerous phylogenetic lineages in close proximity attributed to tectonic induced events.


Lizards , Phylogeny , Animals , Asia , DNA, Mitochondrial , Iran
11.
Mol Phylogenet Evol ; 84: 85-100, 2015 Mar.
Article En | MEDLINE | ID: mdl-25527984

The phylogeny and historical demography of small Eurasian vipers of the Vipera ursinii and V. renardi complexes were studied using mitochondrial DNA sequences analysed with Bayesian inference, Maximum Likelihood and Maximum Parsimony approaches, and mismatch distributions. Diversification in the group resulted from an initial dispersion in the later Pliocene - Pleistocene in two directions: north-westwards via the Balkans (V. ursinii complex) and north-eastwards from Asia Minor via the Caucasus (V. renardi complex). An independent, comparatively recent transition occurred from montane habitats to lowland grasslands in different mitochondrial lineages during the Late Pleistocene, when representatives of the both complexes had reached lowland steppes to the north. Effective population size showed clear signs of rapid growth in eastern V. renardi, triggered by colonization of vast lowland steppes, but in western V. ursinii complex grew during the Last Glaciation and experienced stabilization in Holocene. Expansion and population growth in lowland lineages of V. renardi was not strongly affected by Pleistocene climatic oscillations, when cold, dry conditions could have favoured species living in open grasslands. The high diversity of closely related haplotypes in the Caucasus and Tien-Shan could have resulted from repetitive expansion-constriction-isolation events in montane regions during Pleistocene climate fluctuations. The mitochondrial phylogeny pattern conflicts with the current taxonomy.


Ecosystem , Phylogeny , Viperidae/classification , Animals , Asia , Bayes Theorem , DNA, Mitochondrial/genetics , Grassland , Haplotypes , Likelihood Functions , Sequence Alignment , Sequence Analysis, DNA
12.
Mol Phylogenet Evol ; 61(2): 400-12, 2011 Nov.
Article En | MEDLINE | ID: mdl-21767655

Eremias, or racerunners, is a widespread lacertid genus occurring in China, Mongolia, Korea, Central Asia, Southwest Asia and Southeast Europe. It has been through a series of taxonomic revisions, but the phylogenetic relationships among the species and subgenera remain unclear. In this study, a frequently studied region of the mitochondrial 16S rRNA was used to (i) reassess the phylogenetic relationships of some Eremias species, (ii) test if the viviparous species form a monophyletic group, and (iii) estimate divergence time among lineages using a Bayesian relaxed molecular-clock approach. The resulting phylogeny supports monophyly of Eremias sensu Szczerbak and a clade comprising Eremias, Acanthodactylus and Latastia. An earlier finding demonstrating monophyly of the subgenus Pareremias is corroborated, with Eremias argus being the sister taxon to Eremias brenchleyi. We present the first evidence that viviparous species form a monophyletic group. In addition, Eremias przewalskii is nested within Eremias multiocellata, suggesting that the latter is likely a paraphyletic species or a species complex. Eremias acutirostris and Eremias persica form a clade that is closely related to the subgenus Pareremias. However, the subgenera Aspidorhinus, Scapteira, and Rhabderemias seem not to be monophyletic, respectively. The Bayesian divergence-time estimation suggests that Eremias originated at about 9.9 million years ago (with the 95% confidence interval ranging from 7.6 to 12 Ma), and diversified from Late Miocene to Pleistocene. Specifically, the divergence time of the subgenus Pareremias was dated to about 6.3 million years ago (with the 95% confidence interval ranging from 5.3 to 8.5 Ma), which suggests that the diversification of this subgenus might be correlated with the evolution of an East Asian monsoon climate triggered by the rapid uplift of the Tibetan Plateau approximately 8 Ma.


DNA, Mitochondrial/genetics , Evolution, Molecular , Lizards/genetics , Phylogeny , RNA, Ribosomal, 16S/genetics , Animals , Asia , Bayes Theorem , Europe , Genes, rRNA , Lizards/classification , Models, Genetic , Sequence Analysis, DNA
14.
Science ; 330(6010): 1503-9, 2010 Dec 10.
Article En | MEDLINE | ID: mdl-20978281

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.


Biodiversity , Conservation of Natural Resources , Ecosystem , Vertebrates , Amphibians , Animals , Birds , Endangered Species/statistics & numerical data , Endangered Species/trends , Extinction, Biological , Introduced Species , Mammals , Population Dynamics
15.
Mol Phylogenet Evol ; 53(1): 99-112, 2009 Oct.
Article En | MEDLINE | ID: mdl-19460448

The Central Asian agamid lizards are ecologically and morphologically diverse, occurring across a broad range of desert environments in this biogeographically important region. It is probable that past climatic shifts have significantly influenced the diversification patterns and distributions of the agamid lizards of this region. To assess this within a phylogenetic framework we sequenced a approximately 1200 bp region of mitochondrial DNA and a approximately 1200 bp nuclear gene (RAG-1), incorporating both inter- and intraspecific sampling across Central Asian agamids. Our topology and divergence time estimates support an Eocene origin of the Agaminae subfamily on the Indian subcontinent, coinciding with the collision of India into Eurasia. The onset of aridification in Central Asia during the Late Oligocene, resulting from the retreat of the Paratethys Sea and the intensified uplift of the Tibetan-Himalayan complex, probably played an important role in the diversification of Phrynocephalus, one of the three genera studied. Intensification of aridity and geologic events in the Plio-Pleistocene and Quaternary glacial cycling probably had a significant influence on intraspecific diversification patterns within Phrynocephalus.


Evolution, Molecular , Genetic Speciation , Lizards/genetics , Phylogeny , Animals , Cell Nucleus/genetics , DNA, Mitochondrial/genetics , Desert Climate , Geography , Kazakhstan , Lizards/classification , Sequence Alignment , Sequence Analysis, DNA , Species Specificity , Uzbekistan
17.
Biol Lett ; 2(3): 388-92, 2006 Sep 22.
Article En | MEDLINE | ID: mdl-17148411

Darwin first recognized the importance of episodic intercontinental dispersal in the establishment of worldwide biotic diversity. Faunal exchange across the Bering Land Bridge is a major example of such dispersal. Here, we demonstrate with mitochondrial DNA evidence that three independent dispersal events from Asia to North America are the source for almost all lizard taxa found in continental eastern North America. Two other dispersal events across Beringia account for observed diversity among North American ranid frogs, one of the most species-rich groups of frogs in eastern North America. The contribution of faunal elements from Asia via dispersal across Beringia is a dominant theme in the historical assembly of the eastern North American herpetofauna.


Biodiversity , Lizards/classification , Lizards/genetics , Phylogeny , Ranidae/classification , Ranidae/genetics , Animal Migration , Animals , Biological Evolution , DNA, Mitochondrial/metabolism , Genetic Speciation , Genetic Variation , North America
19.
Mol Phylogenet Evol ; 27(3): 398-409, 2003 Jun.
Article En | MEDLINE | ID: mdl-12742745

We investigated the phylogenetic relationships among most Chinese species of lizards in the genus Phrynocephalus (118 individuals collected from 56 populations of 14 well-defined species and several unidentified specimens) using four mitochondrial gene fragments (12S rRNA, 16S rRNA, cytochrome b, and ND4-tRNA(LEU)). The partition-homogeneity tests indicated that the combined dataset was homogeneous, and maximum-parsimony (MP), neighbor-joining (NJ), maximum-likelihood (ML) and Bayesian (BI) analyses were performed on this combined dataset (49 haplotypes including outgroups for 2058bp in total). The maximum-parsimony analysis resulted in 24 equally parsimonious trees, and their strict consensus tree shows that there are two major clades representing the Chinese Phrynocephalus species: the viviparous group (Clade A) and the oviparous group (Clade B). The trees derived from Bayesian, ML, and NJ analyses were topologically identical to the MP analysis except for the position of P. mystaceus. All analyses left the nodes for the oviparous group, the most basal clade within the oviparous group, and P. mystaceus unresolved. The phylogenies further suggest that the monophyly of the viviparous species may have resulted from vicariance, while recent dispersal may have been important in generating the pattern of variation among the oviparous species.


DNA, Mitochondrial/genetics , Lizards/classification , Phylogeny , Animals , Bayes Theorem , China , Cluster Analysis , Geography , Likelihood Functions , Lizards/genetics
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