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Although several phylogeographic studies of Asian snakes have been conducted, most have focused on pitvipers, with non‐venomous snakes, such as colubrids or natricids, remaining poorly studied. The Chinese keelback water snake (Trimerodytes percarinatus Boulenger) is a widespread, semiaquatic, non‐venomous species occurring in China and southeastern Asia. Based on mitochondrial DNA (mtDNA) and single nucleotide polymorphism (SNP) data, we explored the population genetic structure, genetic diversity, and evolutionary history of this species. MtDNA‐based phylogenetic analysis showed that T. percarinatus was composed of five highly supported and geographically structured lineages. SNP‐based phylogenetic analysis, principal component analysis, and population structure analysis consistently revealed four distinct, geographically non‐overlapping lineages, which was different from the mtDNA‐based analysis in topology. Estimation of divergence dates and ancestral area of origin suggest that T. percarinatus originated ~12.68 million years ago (95% highest posterior density: 10.36–15.96 Mya) in a region covering southwestern China and Vietnam. Intraspecific divergence may have been triggered by the Qinghai‐Xizang Plateau uplift. Population demographics and ecological niche modeling indicated that the effective population size fluctuated during 0.5 Mya and 0.002 Mya. Based on the data collected here, we also comment on the intraspecific taxonomy of T. percarinatus and question the validity of the subspecies T. p. suriki. [ABSTRACT FROM AUTHOR]

Viridovipera stejnegeri is one of the most common pit vipers in Asia, with a wide distribution in southern China and Vietnam. We investigated historical demography and explored how the environment and climatic factors have shaped genetic diversity and the evolutionary history of this venomous snake. A total of 171 samples from 47 localities were sequenced and analysed for two mitochondrial gene fragments and three nuclear genes. Gene trees reveal the existence of two well-supported clades (Southwest China and Southeast China) with seven distinct and strongly supported, geographically structured subclades within V. stejnegeri. Estimation of divergence time and ancestral area suggests that V. stejnegeri originated at ~6.0 Ma in the late Miocene on the Yunnan-Guizhou Plateau. The estimated date of origin and divergence of the island populations of Taiwan and Hainan closely matches the geological origin of the both islands. The mt DNA gene tree reveals the presence of west-east diversification in V. stejnegeri populations. Complex orogenesis and heterogeneous habitats, as well as climate-mediated habitat differentiation including glacial cycles, all have influenced population structure and the distribution of this taxon. The validity of V. stejnegeri chenbihuii is questionable, and this subspecies most probably represents an invalid taxon. [ABSTRACT FROM AUTHOR]

Abstract: The cao vit gibbon (Nomascus nasutus) is among the most endangered primates in the world. The only surviving population lives in a karst forest patch along the China–Vietnam border. In this study, we used high-resolution satellite images to evaluate the habitat quality of the gibbon in the area immediately surrounding the last population and predict the potential gibbon habitat. We then used Vortex to simulate population responses to changes in the habitat’s carrying capacity. Our results showed the gibbon population is approaching the carrying capacity of their current habitat, and carrying capacity has a significant impact on population changes. Two potential habitats were located in a forest connected to the current habitat by a narrow forest corridor, situated above an underground river. Based on the results, we recommend: (1) prohibiting agriculture and grazing activities within the current gibbon habitat; (2) expanding the Cao Vit Gibbon Conservation Area in order to protect potential cao vit habitats in Vietnam; (3) protecting forest corridor that connect the current cao vit habitat to potential habitats; and (4) rehabilitating the forests currently depauperate of important food species in order to support the expansion of both the gibbon population and the range. This research both provides important insight into sustaining the current gibbon population as well as suggestions for both Vietnamese and Chinese local governments planning habitat restoration at the study site. [Copyright &y& Elsevier]

The Asian monotypic genus Pararhabdophis Bourret, 1934 has long been known from a single holotype of the type species Pararhabdophis chapaensis Bourret, 1934 only. The limited available information hampered the identification of the natricine species. On the basis of eight newly collected specimens of P. chapaensis from the type locality in Sa Pa, Lao Cai Province, Vietnam and from Pingbian, Yunnan Province in southwestern China, the taxonomic position of the genus Pararhabdophis was re-evaluated using both morphological and molecular datasets for the first time. Pararhabdophis chapaensis is nested within the genus Hebius Thompson, 1913 with strong support, and morphologically indistinguishable from the latter genus. As a consequence, we herein synonymize the genus Pararhabdophis with Hebius and discuss about the existing paraphyly of some Hebius species. In addition we report Hebius chapaensis for the first time from China and provide redescription and natural history data of this poorly known species. To facilitate future taxonomic work, an identification key to all known natricine genera from China and Vietnam is also provided.