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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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During a trip to Taiwan in May 2018, an Austrian team of herpoetologists recorded three different species of lizards in various habitats. While the mountain dweller Takydromus hsuehshanensis was found in gravel slopes and dump sites above 1.800 m, T. kuehnei was recorded in small clearings and forest margins in the transition zone between planes and hills. Finally T. viridipunctatus was found in gardens and parks in the North of the country near the coast.

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From the perspectives of biodiversity conservation and management, there is an urgent need to have at hand current synopses of classification and distributions of species. In this paper, we review and summarize the classifications, Chinese and English names, type specimens, type localities and distributions of China’s lizard fauna to promote scientific exchange and species conservation among relevant people in China and internationally. As of December 31, 2020, a total of 230 species of lizard, belonging to 44 genera and 12 families, have been recorded from China, including 4 invasive species: 2 in the family Gekkonidae, 1 in Iguanidae and one in Dactyloidae. There are 115 endemic species, accounting for 50% of this group. The proportion of endemic species to China was the highest in the family Eublepharidae (84.62%), and the number of endemic species to China was the highest in the family Agamidae (42 species). The species distributions and classification in the “Fauna Sinica (Reptilia 2): Squamata (Lacertilia)” were updated. Among the provincial administrative units, there is a larger number of species in the southern provinces, such as Yunnan, Guangdong, Guangxi and Taiwan. Sichuan, Yunnan, and Taiwan harbour relatively more endemic species than others. A total of 154 species of lizards were first discovered in China, and the type localities of these species are concentrated in Yunnan, Taiwan, Tibet, Xinjiang, and Sichuan.

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The geographic distribution of species can be affected by environmental factors. The adult highaltitude lizard Takydromus hsuehshanensis (altitude > 1800 m) has been shown to tolerate summer lowland air temperature; its absence in lowland areas may therefore be caused by other factors. We employed a transplant experiment to monitor survival in different life stages and female reproduction in lowland areas. We maintained the T. hsuehshanensis adults in semi-natural outdoor enclosures with sufficient food, water, and the exclusion of potential predators. The results showed that (1) the survival rates of adults gradually decreased to 23.4% from one summer to the next, (2) illness occurred in adults during the winter, and (3) reproductive capacity (2 eggs/female), hatching success (31.7%), and hatchling survival rate (0% at the end of 11 weeks) were very low during the active season. We suggest that environmental factors synergistically caused these impairments in T. hsuehshanensis across different life stages and different seasons. This may partially explain its current altitudinal distribution.

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1. We investigated whether heat tolerance has a crucial impact on the altitudinal distribution of a high-altitude lizard, Takydromus hsuehshanensis (>1800 m altitude). 2. We measured and compared its heat tolerance with that of another two lowland species. Heat tolerance measurement included critical thermal maximum (CTMax) and survival rates under three fluctuating daily temperature treatments over a 3-month period. Two of the three temperature treatments, the extremely high temperature (EH treatment) and the average temperature (H treatment), were set to approximate lowland summer temperatures. The third one was set to approximate cool temperature in mountain areas (C treatment). 3. Our results showed that (1) CTMax of T. hsuehshanensis was higher than the summer temperature in the lowland areas, and not significantly lower than that of two other lowland species, (2) T. hsuehshanensis survived the H and EH treatments over a 3-month period and its survival rate was not significantly lower than that of the other two lowland species. Therefore, T. hsuehshanensis was not only able to tolerate high temperatures mimicking lowland areas for a short period of time, but also for a much longer period of time. 4. We conclude that the heat tolerance of T. hsuehshanensis is not a crucial factor limiting its current altitudinal distribution.

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We investigated whether cold tolerance was an important limiting factor in the current altitudinal distributions of two Takydromus lizards, T. formosanus (< 1500 m in altitude) and the lowland-dwelling T. stejnegeri (< 1000 m in altitude) in Taiwan. We measured their critical thermal minimum (CTMin) and 3 mo survival rates in 4 cold treatments, and compared these with a high-mountainous species, T. hsuehshanensis (> 1800 m in altitude). The results indicated that (1) both the CTMin and prolonged cold tolerance were correlated to their upper limit of altitudinal distributions as predicted and (2) T. formosanus and T. stejnegeri had reasonable survival rates at temperatures that were lower than the underground temperature of high altitudinal areas. We concluded that although cold tolerance was correlated with altitudinal distribution, it is not a crucial factor limiting T. formosanus and T. stejnegeri at higher altitudes.

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We investigated the impact of environmental temperature on elevational distributions of a high-mountainous lizard, Takydromus hsuehshanensis, by examining the thermal sensitivity of its locomotor performance. Its sprint speed was measured at 9 body temperatures after 2 wk of acclimation at 2 different temperatures. The same measurements were performed on a closely related species, T. formosanus, which lives at lower elevations. The results indicated that (1) T. hsuehshanensis was capable of maintaining normal locomotor performance within a body temperature range which approximates summer temperatures of lowland areas; (2) T. formosanus was able to run significantly faster than T. hsuehshanensis within a certain range of body temperatures; (3) these 2 species did not differ in their thermal sensitivities of the locomotor performance; and (4) temperature acclimation treatments did not affect the locomotor performance of these 2 species. We concluded that locomotor performance is not a crucial factor limiting the distribution of T. hsuehshanensis in lowland areas.

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Warmer climates have affected animal distribution ranges, but how they may interact with vegetation patterns to affect habitat use, an important consideration for future wildlife management, has received little attention. Here, we use a biophysical model to investigate the potential thermal impact of vegetation pattern on the habitat quality of a high-elevation grassland lizard, Takydromus hsuehshanensis, and to predict the thermal suitability of vegetation for this species in a future warmer climate (assuming 3 °C air temperature increase). We assess the thermal quality of vegetation types in our study area (Taroko National Park in areas >1,800 m) using three ecologically relevant estimates of reptiles: body temperature (T b), maximum active time, and maximum digestive time. The results show that increasing forest canopy gradually cools the microclimates, hence decreasing these estimates. In the current landscape, sunny mountain-top grasslands are predicted to serve as high quality thermal habitat, whereas the dense forests that are dominant as a result of forest protection are too cold to provide suitable habitat. In simulated warmer climates, the thermal quality of dense forests increases slightly but remains inferior to that of grasslands. We note that the impact of warmer climates on this reptile will be greatly affected by future vegetation patterns, and we suggest that the current trend of upslope forest movement found in many other mountain systems could cause disadvantages to some heliothermic lizard species.

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In this study, I describe seasonal variations in the male and female reproductive cycles of Takydromus hsuehshanensis, an oviparous grass lizard endemic to the high altitude areas of Taiwan. Mean snout-vent length (SVL) of adult males (n = 78) and females (n = 105) were 60.5 mm (range = 47-72 mm) and 61.2 mm (range = 54-72 mm), respectively. Females exhibited a spring vitellogenic period with parturition occurring in May to July. The onset of vitellogenesis showed a negative correlation with the mass of the female fat body. Females produced two to four eggs per clutch, and clutch size was positively correlated with SVL: only females with SVLs equal to or larger than 61 mm produced a clutch consisting of four eggs. Two clutches were recorded during a single year in some individuals. Males exhibited a continuous spermatogenic pattern, but testis mass, accessory sexual organ mass, and seminiferous tubule diameter showed cyclical changes with a peak before the dormant months from September to December. The tubules of the epididymides were full of sperm from December to the following March, indicating that sperm were stored in the epididymides until the occurrence of ovulation in the spring. Male fat bodies exhibited the lowest mass from March to June, coincident with the period of reproductive activity. Male seminiferous tubule diameter exhibited a positive correlation with liver, fat body, and testis masses. However, seminiferous tubule diameter, as well as testes mass, had a negative correlation with precipitation. Timing of reproduction in four other sympatric lizards and clutch size variation in other Takydromus species are compared with those in T. hsuehshanensis.

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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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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.