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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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Anticipatory behaviour is the expectation of a near-future event based on information processed in the past and influences an animal’s tactical decisions, particularly when there are significant fitness consequences. The grass lizard (Takydromus viridipunctatus) perches on blades of grass at night which likely reduces the probability of predation by terrestrial preda- tors such as snakes, rodents and shrews. During twilight (starting 30 min before sunrise), they move from above the grass to within grass clumps and this is thought to afford the lizard protection while reducing detection by avian predators. Here, we examined how lizards shift their behaviour as a function of visual detectability to their primary predator, the cattle egret (Bubulcus ibis). We show that the lizards shift from their perch site during twilight at the earliest time at which egrets depart communal roosts. At the same time, visual modelling shows a dramatic increase in the detectability of the lizards to the visual system of egrets. Therefore, anticipatory behaviour in response to environmental cues acts to reduce pre- dation risk as lizards become more conspicuous and predators become more active. Grass lizard anticipatory behaviour appears to be finely tuned by natural selection to adjust to temporal changes in predation risk.

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Based on 20,000 records representing c. 11,000 individuals from an 8-year capture-mark-recapture (CMR) study, we tested and confirmed a new case of invariant clutch size (ICS) in a sexually dichromatic lacertid lizard, Takydromus viridipunctatus. In the grassland habitat of the early succession stage, females showed strictly low and invariant clutch size, multiple clutches in a breeding season, high reproductive potential, and annual breeding cycles that correspond to the emergence of male courtship coloration. The hatchlings mature quickly, and join the adult cohort for breeding within a few months, whereas adults show low survival rates and a short lifespan, such that most die within one year. Mortality increased in both sexes during the breeding season, especially in females, indicating an unequal cost of reproduction in survival. These life history characters may be explained by two nonexclusive hypotheses of ICS—arboreal hypothesis and predation hypothesis—within the ecological context of their habitat. Our study highlights a confirmed case of ICS, which adapts well to this r-selected grassland habitat that experiences seasonal fluctuation and frequent disturbance.

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Caudal autotomy in lizards has intrigued scientists for more than 100 years. Because of the relative lack of literature under natural conditions, the complicated association among field autotomy rate, real predation pressure, the long-term cost of tail loss, and the benefit of regeneration remains equivocal. In this study, we conducted a 7-year capture–mark–recapture (CMR) programme with a wild population of a sexually dichromatic lizard, Takydromus viridipunctatus. We used autotomy indexes and a contemporary bird census mega-dataset of four predatory birds as predictors to examine the association between tail loss and predation pressure. We further estimated the survival cost of tail loss and alleviation by regeneration under natural conditions through CMR modelling. We found that large and small avian predators affect lizard survival through the following two routes: the larger-sized cattle egret causes direct mortality while the smaller shrikes and kestrels are the major causes of autotomy. Following autotomy, the survival rate of tailless individuals over the next month was significantly lower than that of tailed individuals, especially males during the breeding season, which showed a decline of greater than 30%. This sex-related difference further demonstrated the importance of reproductive costs for males in this sexually dichromatic species. However, the risk of mortality returned to baseline after the tails were fully grown. This study indicates the benefit of tail regeneration under natural conditions, which increases our understanding of the cost–benefit dynamics of caudal autotomy and further explains the maintenance of this trait as an evolutionarily beneficial adaption to long-term predator–prey interactions.

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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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Heterozygosity-fitness correlations (HFCs) provide insights into the genetic bases of individual fitness variation in natural populations. However, despite decades of study, the biological significance of HFCs is still under debate. In this study, we investigated HFCs in a large population of the sexually dimorphic lizard Takydromus viridipunctatus (Lacertidae). Because of the high prevalence of parasitism from trombiculid mites in this lizard, we expect individual fitness (i.e., survival) to decrease with increasing parasite load. Furthermore, because morphological asymmetry is likely to influence individuals` mobility (i.e., limb asymmetry) and male biting ability during copulation (i.e., head asymmetry) in this species, we also hypothesize that individual fitness should decrease with increasing morphological asymmetry. Although we did not formally test the relationship between morphological asymmetry and fitness in this lizard, we demonstrated that survival decreased with increasing parasite load using a capture-mark-recapture data set. We used a separate sample of 140 lizards to test the correlations between individual heterozygosity (i.e., standardized mean d2 and HL based on 10 microsatellite loci) and the two fitness traits (i.e., parasite load and morphological asymmetry). We also evaluated and excluded the possibility that single-locus effects produced spurious HFCs. Our results suggest male-only, negative correlations between individual heterozygosity and parasite load and between individual heterozygosity and asymmetry, suggesting sex-specific, positive HFCs. Male T. viridipunctatus with higher heterozygosity tend to have lower parasite loads (i.e., higher survival) and lower asymmetry, providing a rare example of HFC in reptiles.

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Expression of nuptial color is usually energetically costly, and is therefore regarded as an ‘honest signal’ to reflect mate quality. In order to choose a mate with high quality, both sexes may benefit from the ability to precisely evaluate their mates through optimizing visual systems which is in turn partially regulated by opsin gene modification. However, how terrestrial vertebrates regulate their color vision sensitivity is poorly studied. The green-spotted grass lizard Takydromus viridipunctatus is a sexually dimorphic lizard in which males exhibit prominent green lateral colors in the breeding season. In order to clarify relationships among male coloration, female preference, and chromatic visual sensitivity, we conducted testosterone manipulation with mate choice experiments, and evaluated the change of opsin gene expression from different testosterone treatments and different seasons. The results indicated that males with testosterone supplementation showed a significant increase in nuptial color coverage, and were preferred by females in mate choice experiments. By using quantitative PCR (qPCR), we also found that higher levels of testosterone may lead to an increase in rhodopsin-like 2 (rh2) and a decrease in long-wavelength sensitive (lws) gene expression in males, a pattern which was also observed in wild males undergoing maturation as they approached the breeding season. In contrast, females showed the opposite pattern, with increased lws and decreased rh2 expression in the breeding season. We suggest this alteration may facilitate the ability of male lizards to more effectively evaluate color cues, and also may provide females with the ability to more effectively evaluate the brightness of potential mates. Our findings suggest that both sexes of this chromatically dimorphic lizard regulate their opsin expression seasonally, which might play an important role in the evolution of nuptial coloration.

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To better understand how an animal’s physiological regulation of the immune system can shift in response to a physical stressor, we investigated changes in immune function and circulating plasma testosterone in response to a cutaneous wound in male grass lizards (Takydromus viridipunctatus).