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Aim: Global warming and deforestation are pushing species closer to their physiological limit, especially for species with habitat‐restricted life stages because sunlit areas have higher maximum temperatures. Here, we examined the critical thermal maximum (CTmax), and maximum environmental water temperature (Tmax) of larvae from 29 anuran species across a latitudinal gradient (22–43° N) to test how latitude and habitat type (open or closed‐forest ponds) affected warming tolerance, an index of vulnerability to climate change. Location: Taiwan, Korea, Japan. Time period: Present. Major taxa studied: Anurans. Results: We showed that open ponds lowered warming tolerance, regardless of latitude and phylogenetic clustering, contrasting the established literature that warming tolerance is lower at tropical latitudes, which only applied to species in forest ponds in this study. Importantly, biophysical models at the local scale suggest that increasing deforestation will exacerbate the effects of climate warming on warming tolerance. Main conclusions: Local effects of accelerated warming and habitat modification mean that species with range‐restricted life stages will become more vulnerable to anthropogenic change. [ABSTRACT FROM AUTHOR]

Simple Summary: Thermal tolerance can help understand species' response to climate change, but regional scale data is missing. We filled this gap by investigating intraspecific variations in the critical thermal maximum (CTmax) of Rana uenoi tadpoles collected from rice paddies and Bufo sachalinensis tadpoles collected from lakes, over a five-degree latitudinal gradient. We found a positive relationship between latitude and CTmax in R. uenoi tadpoles, although they did not display specific thermoregulatory behaviors. In contrast, none of the abiotic factors were related to CTmax in B. sachalinensis, but the tadpoles swam closer to the water surface when water temperature increased. Thus, R. uenoi displays a physiological adaptive response while B. sachalinensis behaviorally thermoregulate. This is important as species specific responses to climate change have to be understood for their conservation. Although thermal tolerance along geographical gradients gives an insight into species' response to climate change, current studies on thermal tolerance are strongly skewed towards global-scale patterns. As a result, intraspecific variations are often assumed to be constant, despite a lack of evidence. To understand population-specific responses to thermal stress, we investigated the presence of intraspecific variations in the critical thermal maximum (CTmax) of tadpoles in two anuran species, Rana uenoi and Bufo sachalinensis. The study was conducted across a five-degree latitudinal gradient in the Republic of Korea. We exposed the tadpoles to increasing temperatures and recorded the CTmax for 270 R. uenoi individuals from 11 sites, collected in rice paddies, and for 240 B. sachalinensis individuals from ten sites, collected in reservoirs. We also recorded the swimming performance and behavior of the tadpoles when placed in an experimental apparatus during CTmax measurements. We then used linear regressions to determine the relationship between abiotic factors and CTmax. In R. uenoi, we found a positive relationship between latitude and CTmax, but the tadpoles did not display specific thermoregulatory behaviors. In B. sachalinensis, none of the abiotic factors such as climate and geographic coordinates were related to CTmax, but we detected a tendency to swim close to the water surface when water temperature was increasing. For R. uenoi, we tentatively relate the CTmax variability across the latitudinal gradient to a physiological adaptive response associated with habitat characteristics that are assumed to be fluctuating, as the species inhabits small water bodies prone to drying out. In the case of B. sachalinensis, the behavior observed may be linked to oxygen depletion and thermoregulation, as it may buffer temperature changes in the absence of physiological adjustment. These findings suggest that intra-specific variations in CTmax are greater than generally accounted for, and thermal conditions of natural environments are important for understanding thermal tolerance in ectothermic species. Our results highlight that species' specific responses to climate warmings need to be studied to better protect species against climate change. [ABSTRACT FROM AUTHOR]

While comparatively few amphibian species have been described on the North East Asian mainland in the last decades, several species have been the subject of taxonomical debates in relation to the Yellow sea. Here, we sampled Dryophytes sp. treefrogs from the Republic of Korea, the Democratic People's Republic of Korea and the People's Republic of China to clarify the status of this clade around the Yellow sea and determine the impact of sea level change on treefrogs' phylogenetic relationships. Based on genetics, call properties, adult morphology, tadpole morphology and niche modelling, we determined the segregated status species of D. suweonensis and D. immaculatus. We then proceeded to describe a new treefrog species, D. flaviventris sp. nov., from the central lowlands of the Republic of Korea. The new species is geographically segregated from D. suweonensis by the Chilgap mountain range and known to occur only in the area of Buyeo, Nonsan and Iksan in the Republic of Korea. While the Yellow sea is the principal element to the current isolation of the three clades, the paleorivers of the Yellow sea basin are likely to have been the major factor for the divergences within this clade. We recommend conducting rapid conservation assessments as these species are present on very narrow and declining ranges. [ABSTRACT FROM AUTHOR]

Predation risk is among the key forces driving the evolution of escape behaviours and related phenotypes. Successful avoidance of predators results in increased survival rate and fitness. The behavioural response of individuals under predation pressure has been comparatively well studied, however, most studies focus on specific escape behaviours and not on behavioural plasticity. The American bullfrog (Lithobates catesbeianus) has been an invasive species in the Republic of Korea since the 1970s and has a negative impact on local species. Here, we evaluated the functions of microhabitat preference and behavioural plasticity in L. catesbeianus tadpoles through manipulative experiments. In a first experiment, we placed wildcaught tadpoles with a local predatory fish (Channa argus) into one of three microhabitat treatments: non-vegetated, submerged vegetation, or floating vegetation. The survival rate of tadpoles with submerged vegetation was significantly higher than that in the non-vegetated microhabitat. In contrast, the survival rates of tadpoles with floating vegetation was not significantly different from the two other treatments. In the habitat preference experiment, "unhurt" and "wounded" wildcaught tadpoles were given a choice between the three microhabitat treatments. Both types of tadpoles preferentially selected the submerged vegetation microhabitat compared to the non-vegetated microhabitat. In contrast, only wounded tadpoles significantly preferred floating vegetation over non-vegetated microhabitats. We conclude that L. catesbeianus tadpoles prefer vegetated microhabitats, and especially submerged vegetation. Furthermore, L. catesbeianus tadpoles can adjust their antipredatory behaviour according to previous experience, and thus demonstrate behavioural plasticity by using microhabitats that they do not use in the absence of predators. [ABSTRACT FROM AUTHOR]