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The east Asian lacertid lizard genus,Takydromus, is well-defined but its relationships to other primitive Palaearctic lacertids are still uncertain and, although it has similarities to the lower Miocene Miolacerta, Takydromus does not appear to be identical with this. The 16 or 17 recognizable species are reviewed and a key provided for their identification; the remaining area of uncertainty about species boundaries is the Takydromus sexlineatus group in Assam. A phylogeny forTakydromusis estimated using a data set of 35 morphological characters drawn from external features, skeleton and soft-parts. There are two main constituent clades which may be informally recognized asTakydromus s.s.and Platyplacopus. Platyplacopusis subtropical and perhaps relict, whereasTakydromus ranges from temperate to tropical areas. The two clades have different ranges of eggs per clutch. In both of them, elongate forms that climb extensively in flimsy vegetation have evolved and have independently acquired similar features that confer performance advantages in this situation. Interestingly, the order of assembly of these features is markedly different.

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The east Asian lacertid lizard genus, Takydromus, is well-defined but its relationships to other primitive Palaearctic lacertids are still uncertain and, although it has similarities to the lower Miocene Miolacerta. Takydromus does not appear to be identical with this. The 16 or 17 recognizable species are reviewed and a key provided for their identification; the remaining area of uncertainty about species boundaries is the Takydromus sexlineatus group in Assam. A phylogeny for Takydromus is estimated using a data set of 35 morphological characters drawn from external features, skeleton and soft-parts. There are two main constituent clades which may be informally recognized as Takydromus s.s. and Platyplacopus. Platyplacopus is subtropical and perhaps relict, whereas Takydromus ranges from temperature to tropical areas. The two clades have different ranges of eggs per clutch. In both of them, elongate forms that climb-extensively in flimsy vegetation have evolved and have independently acquired similar features that confer performance advantages in this situation. Interestingly, the order of assembly of these features is markedly different.

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DNA sequence indicates the Lacertidae contain two subfamilies, Gallotiinae and Lacertinae, the latter comprising two monophyletic tribes, the Eremiadini of Africa and arid southwest and central Asia, and the Lacertini of Europe, northwest Africa and southwest and east Asia. Relationships within the 108 species of Lacertini are explored using mtDNA (291 bp cytochrome b; 329 bp 12S rRNA for 59 nominal species, and reanalysis of the data of Harris et al. 1998, and Fu 2000). The morphology of the tribe is reviewed and 64 of its characters (equivalent to 83 binary ones) also used to assess relationships. The Lacertini are assigned to 19 monophyletic units of 1 to 27 species, recognised here as the following genera (contents are indicated in brackets): Algyroides, Anatololacerta gen. nov. (L. danfordi group), Apathya (L. cappadocica group), Archaeolacerta (L. bedriagae), Dalmatolacerta gen. nov. (L. oxycephala), Darevskia (L. saxicola group), Dinarolacerta gen. nov. (L. mosorensis), Hellenolacerta gen. nov. (L. graeca), Iberolacerta (L. monticola group), Iranolacerta gen. nov. (L. brandtii and L. zagrosica), Lacerta s. str. (sand and green lizards, L. agilis group), Parvilacerta gen. nov. (L. parva and L. fraasii), Phoenicolacerta gen. nov. (L. laevis group), Podarcis (wall lizards), Scelarcis (L. perspicillata), Takydromus (Asian grass lizards), Teira (L. dugesii), Timon (ocellated lizards, L. lepida group) and Zootoca (L. vivipara). Both mtDNA and morphology indicate that Lacerta and Timon are sister taxa, and DNA suggests further possible relationships among genera (Fig. 1, p. 6). Neither DNA nor morphology indicates that the archaeolacertas (sometimes formalised as Archaeolacerta sens. lat.) form a clade. Instead, they are representatives of an ecomorph associated with living on rock exposures and using the narrow crevices that these contain. The Lacertidae probably arose in the European area, with the Gallotiinae later reaching Northwest Africa and the Canary Islands, and the ancestor of the Eremiadini invading Africa in the mid-Miocene. The Lacertini spread through much of their present European range and diversified, perhaps largely by repeated vicariance, around 12–16 My ago, producing the ancestors of the present mainly small-bodied genera, which then underwent often modest speciation. Three units spread more widely: the Lacerta-Timon clade of large-bodied lizards probably dispersed earliest, followed by Algyroides and then Podarcis. Overall, European Lacertidae show a pattern of repeated spread, often accompanied by restriction of previous groups. Expansion of Lacertini may have displaced earlier lacertid lineages from all or much of Europe; while spread of Podarcis may have restricted many other genera of Lacertini. The earlier expansion of the Lacerta-Timon clade probably did not have this effect, as difference in adult body size restricted competitive interaction with other forms. Several invasions of more distant areas also occurred: of East Asia by Takydromus over 10 My ago, and more recently of northwest Africa by Podarcis, Scelarcis and Timon, and Madeira by Teira. Relationships within the Eremiadini estimated from both mtDNA, and nDNA differ considerably from those based on morphology. They indicate relatively mesic forms may have diversified widely across Africa and given rise to at least three independent invasions of arid habitats. MtDNA also indicates that Lacerta andreanskyi belongs in the Eremiadini and may occupy a basal position there. It is assigned to a further new genus, Atlantolacerta gen. nov.

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Cytochrome b (cyt b) gene complete sequences (1143bp) of Takydromus sylvaticus were sequenced. In order to clarify the phylogenetic position of the Takydromus sylvaticus, we investigated the phylogeny of 15 Takydromus spp. distributed in East-Asia by Maximum Parsimony (MP), Bayesian Inference (BI), and Maximum Likelihood (ML) methods using DNA fragments of cyt b genes. The results supported that the Platyplacopus merged into Takydromus and negated the validity of Platyplacopus. Furthermore, the prediction of tertiary structures of cyt b exhibited the CD loop region contain two short helices forming a hairpin arrangement, namely cd1 and cd2. Thermostability analysis shows that the CD-loop region is unstable thermodynamically and may provide mobility to amino acids located at the heme, and might provide high flexibility to the top of ISP (iron–sulfur protein) and the cavity region of Qo binding site. It suggested that the two short helices of CD loop region of cyt b was a dominating portion for ISP binding site.

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Rare or newly discovered species are attractive targets for poaching as they often command a high value in the international market. Endemic species often have a very restricted range, making them extremely vulnerable to stochastic events and human activities, including poaching. Previous studies have shown that several species endemic to the Nansei Islands in Japan are available in the international pet trade. This paper further investigates the presence of live reptiles and amphibians endemic to the Nansei Islands in international pet trade. Seven Facebook groups and five classified websites were searched for these species, in addition to the CITES database and a spot-check at Chatuchak market in Thailand. Nansei Island endemic reptiles and amphibians are more common in the international pet trade than initially thought. During the study period, advertisements for 23 species endemic to the Nansei Islands were found, comprising a total of 360 specimens. In addition, during a spot-check, 8 individuals of 2 subspecies of Japanese sword-tail newt were found at Chatuchak market in Thailand. Only three of these species are protected by the CITES and nine are regionally or nationally protected. Yet, ten species observed in international markets are classified as Endangered by IUCN and two even as Critically Endangered. The large numbers observed for the Endangered and Critically Endangered Goniurosaurus and Takydromus species warrants increased protection and a CITES Appendix III listing is recommended for these species.

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Brown and green are the most commonly imitated colors in prey animals because both colors occur in a range of habitats. Many researchers have evaluated survival with respect to background color matching, but the pigment cell mechanisms underlying such coloration are not known. Dorsal coloration of East Asian Takydromus lizards has shifted from green to brown or from brown to green on multiple occasions during the diversification of the genus, thus giving us an opportunity to examine the cellular mechanisms of background color matching. Brown and green skin were found to differ with respect to the morphological characteristics of iridophores, with different thicknesses of the reflecting platelets and the cytoplasmic spacing between platelets, despite a shared vertical arrangement of pigment cells, i.e., xanthophores in the upper layer, iridophores in the middle layer, and melanophores at the bottom of the dermal layer, among the different Takydromus lizards. Iridophores of brown skin reflected longer wavelengths of light than those of green skin, which may be attributed to the thicker platelets and longer distances between platelets in brown skin. We discuss the potential role of genetic and intracellular mechanisms explaining the thickness and orientation of the light-reflecting platelets of iridophores in Takydromus lizards.

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Takydromus Daudin is a group of Lacertidae lizards with slender bodies and long tails. Half of the Takydromus spp. are endemic to islands of eastern Asia aligned along the Pacific margin of the East Asian continent. This feature offers a good opportunity to study the effects of glaciations and land connections on the speciation of East Asian fauna. We reconstructed the molecular phylogeny of Takydromus species via the mitochondrial 12S rRNA gene. Phylogenetic analyses using maximum-parsimony, neighborjoining, and maximum-likelihood options do not support a two-subgenera scheme of Takydromus and Platyplacopus proposed earlier. In contrast, the phylogeny of Takydromus species on islands fits the sequential separation of island groups influenced by changes in sea level. The hypothesis in our prediction supports the process of vicariant speciation and multicolonization of grass lizards on eastern Asian islands. At least two obvious colonization events were followed by vicariance events. Because the molecular clock of the 12 rRNA gene was not rejected in our model test, it is possible to estimate times of speciation events. As the most isolated and basal species compared to other temperate and subtropical species of Takydromus, the separation period of T. smaragdinus in the central Ryukyus is the crucial point in estimating the evolutionary rate. Quaternary-origin or Tertiary-origin models are proposed and discussed

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Two new grass lizard species, previously confused with Takydromus formosanus, were identified in Taiwan using mitochondrial DNA sequences. In the present study, 40 morphological characters and their taxonomic significances were assessed using principal components analysis and discriminant analysis. The three species can be distinguished by morphology of body sizes, dorsal and caudal scales, and most importantly, by male coloration during the breeding seasons. The present study increases the total number of Takydromus to 19 species, of which 10 are insular endemics, with six only occurring in Taiwan.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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Thermal reaction norms of sprint speed were examined in three lacertid lizard species (Takydromus tachydromoides, T. smaragdinus, and T. dorsalis). We found inter- and intraspecific variations in maximum sprint speed, optimal body temperature, and thermal performance breadth for the best sprints. The thermal performance breadth of T. smaragdinus was broader than that of T. tachydromoides or T. dorsalis, whereas T. dorsalis sprinted faster than the others. In T. smaragdinus, individuals with narrower performance breadths run faster within their thermal range of expertise. There were “specialist” individuals of which performance depended heavily on high temperatures, as well as “generalist” individuals that performed well over a broad range of temperatures even within a single population. We discussed that the spatiotemporal instability of habitats might favor more than one type of thermal reaction norm of sprint performance, and this phenomenon may be driven by specialist–generalist trade-offs.

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This paper analyzes the phylogeographical patterns of amphibian and reptile lineages distributed in the Ryukyu islands south of the Tokara Gap on the basis of relevant distributional data and phylogenetic hypotheses hitherto published. Results indicate the numerical dominance of highly relict lineages in the central Ryukyus, and the occurences of a few more or less relict lineages in the Miyako Group as well. On the other hand, most species and subspecies endemic to the Yaeyama Group or to the Yaeyama and Miyako Groups are considered to be direct consequences of vicariance with adjacent regions. Three major hypotheses regarding the Cenozoic paleogeography of the central and the southern Ryukyus are examined in the light of the present results and a modified hypothesis is proposed accordingly.

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Historical relationships were inferred for the oriental lizards of the genus Takydromus Daudin 1802 (Lacertidae) on the basis of DNA sequences. Of the 17 species currently recognized for the genus, 13 species represented by 42 specimens from 29 localities were examined. Maximum-likelihood and maximum-parsimony analyses of data for 829 aligned sites from parts of the mitochondrial 12S and 16S rRNA genes yielded relationships that, while showing no substantial discrepancy with each other, were strikingly different from a currently prevailing phylogenetic hypothesis from a parsimony analysis of morphological characters. Based on the results of these molecular analyses, supplemented by results of the morphological analysis that offered robust evidence for positions of two additional species (T. khasiensis and T. sylvaticus), the following interrelationships were hypothesized as the most preferred phylogeny: (kuehnei (sexlineatus khasiensis))(tachydromoides ((smaragdinus (sauteri (dorsalis sylvaticus))) (amurensis (((formosanus wolteri) hsuehshanensis)(toyamai (septentrionalis stejnegeri)))))). These interrelationships indicate: (1) invalidity of Platyplacopus Boulenger 1917, which was recently resurrected as a subgenus of Takydromus on the basis of the morphological analysis; (2) homoplasy in states of some morphological characters, such as green dorsal coloration, that were considered as synapomorphs of certain nodes in the morphological analysis; and (3) involvement of the genus in a series of vicariances in both the continental and insular parts of eastern Eurasia. Due to the paucity of available samples, phylogenetic status of T. intermedius and T. haughtonianus remain to be examined in future studies.

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The Chung-an ground lizard, Takydromus sylvaticus, long known only from five females collected in Fujian Province of China, was recently found in Anhui Province of the country. The newly collected specimens included the first male specimens (n=7), in which the tail bases were stouter than in conspecific females. Ventral scales in these males were invariably keeled, whereas in females those forming the four median rows were smooth. Females had more dorsal scales (47–48) than males (42–43) in the median longitudinal row between axilla and groin. Takydromus sylvaticus differed from the closely related T. dorsalis in having more dorsal scales in the median longitudinal row between axilla and groin (42–48 versus 32–40, respectively), more rows of large dorsal scales between the hind legs (10 versus 7–8, respectively), shorter hind legs, two distinct white longitudinal stripes on each side of the body, and no black stripe in the preocular and postocular regions. The number of transverse rows of ventral scales between collar and femoral pores in T. sylvaticus(26–28) was larger, but with a slight overlap, than that in T. dorsalis (22–26). Ecological observations on T. sylvaticus were also documented.