Vietnam has the second highest diversity of freshwater mussels (Unionida) in Asia after China. The purpose of this paper is to compile an up-to-date list of the modern unionid fauna of Vietnam and its current conservation status. Unfortunately, there has been relatively little research on this fauna in Vietnam. Fifty-nine species of Unionida have been recorded from Vietnam based on literature, museum records, and our fieldwork. Fifty were assessed in the International Union for Conservation of Nature (IUCN) Red List 2016 in the IUCN categories of Critically Endangered (four species, 6.8%), Endangered (seven species, 12%), Vulnerable (one species, 1.7%), Near Threatened (two species, 3.4%), Least Concern (23 species, 39%), Data Deficient (11 species, 18.6%), and Not Evaluated (11 species, 18.6%). Considering the impacts of pollution, timbering, agriculture, and damming of rivers, research on the diversity and conservation status of freshwater mussels is very urgently needed to propose specific conservation measures for these species in Vietnam. If all taxa listed as Data Deficient are found to be threatened, with around 42% of species threatened, this fauna would be one of the most threatened freshwater molluscan faunas in Asia.

Three short field surveys were conducted in the Phia Oac-Phia Den Nature Reserve to assess the species diversity and endemism of local bat fauna. In combination with data from a previous study, 24 bat species of 5 families, representing > 20% of the national bat diversity, were recorded in the study area. The occurrence of several bat species restricted to montane forests, that is, Murina chrysochaetes, Pipistrellus coromandra, and a potentially new species Rhinolophus cf. macrotis, suggests that Phia Oac is an important area for bat conservation in Vietnam and thus more comprehensive studies need to be performed

Climate and land-cover changes are among major threats to biodiversity. However, the interactive effects of the two threats are often overlooked in conservation planning. Using 81 bat species occurring in Vietnam as a case, we investigated the individual and interactive effects of climate and land-cover changes, highlighting the importance of this information for conservation efforts. By using species distribution models, we predicted the potential changes in range size among species and in species richness across Vietnam by the 2050s, considering projected climate and land-cover changes under two emission scenarios. Our results revealed that both threats individually would have predominantly negative effects on bats in Vietnam. Moreover, when these threats occur simultaneously, their interactions would generally intensify the impacts by mitigating individual positive effects and/or enhancing negative effects. However, we also found large interspecific and geographic variations in the direction and magnitude of these effects. Forest specialists, insectivores and cave-roosting species were predicted to be particularly vulnerable to the negative effects, with northern and southern Vietnam being more affected. These results underscore the urgent need to incorporate both climate and land-cover changes, as well as their interactions, into conservation planning for bats in Vietnam and biodiversity in general. The species-specific and spatially-explicit information regarding the impacts of the two threats can guide conservation actions, allowing us to target more manageable and less uncertain threats, as well as prioritize the protection of more vulnerable species.

The endangered crocodile lizard, Shinisaurus crocodilurus, is seriously imperiled by anthropogenic threats, including habitat loss and degradation and most critically over-collection for the international pet trade. As a result, population sizes of crocodile lizards have sharply declined throughout their range, with only a small number remaining in China and a handful of individuals left in Vietnam. To prioritize conservation measures for the species, in this study, we generate new mitochondrial sequences of important new samples and analyze them with existing data. Our results confirm a new genetically distinct population in China, highlighting cryptic genetic diversity within the species. The assessment of climate change impacts on the species suggests that the suitable habitat of one population in China will become severely fragmented, decreased in size, and shifted, while the habitat of two other Chinese populations will remain stable and may even expand given future climate scenarios. In Vietnam, Yen Tu Mountain Range is predicted to serve as a refuge in different climate change projections, but suitable habitat in the border area between Vietnam and China will likely shift geographically. Based on our results, we recommend further field surveys to locate the natural distribution range of the newly identified molecular clade in China and determine the distribution extension of the Vietnamese population in the border area, especially potential occurrence on the Chinese side. Considering the impacts of climate change on the Vietnamese population, designing a corridor to connect the subpopulation’s habitat in the border area with nature reserves in Yen Tu Mountain Range and/or translocating lizards from the site to more suitable habitats might help secure the subpopulation in the context of climate change. In all recommended conservation measures, close collaboration between Vietnam and China will be crucial to effectively protect this potentially shared subpopulation of the highly threatened species.

Mangrove ecosystems play important ecological roles, including the mitigation of global climate change and biodiversity conservation. However, they have received little attention from scientists for the research and conservation of bats and general biodiversity. In Vietnam, bat species inhabiting mangroves have been relatively unstudied, while this ecosystem is located along the country’s coastal zones and has declined dramatically due to the development of agriculture, wind energy and other threats. To initially fill this gap, five bat surveys were conducted between September 2019 and November 2021 within Ha Long Bay and Ben Tre province, which contain representative mangrove areas of northern and southern regions of Vietnam, respectively. Bats were captured using mist nets, mobile nets and hand nets. Their echolocation calls were recorded and analyzed using the PCTape system and Selena software, respectively. Five species were captured and recorded: Cynopterus brachyotis, Macroglossus minimus, Myotis hasselti, Myotis pilosus and Taphozous melanopogon. They are all new to both Ha Long Bay and Ben Tre province. Four species (C. brachyotis, M. minimus, M. hasselti and M. pilosus) have been rarely documented from other ecosystems in Vietnam but have commonly been recorded and captured in mangrove areas. Of these species, M. pilosus is a globally “Vulnerable” species. While searching for prey, Myotis hasselti emitted high energy echolocation calls sweeping from about 96 to about 24 kHz with a signal duration of about 5 ms. This species sometimes uses social calls of a horseshoe-shaped structure, which last about 15 ms and are emitted about 26 ms in front of a search call. Results from our surveys indicated the importance and potential of mangroves for bat research and conservation.