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Another new species of Dixonius, D. fulbrighti sp. nov., is described from Gia Lai Province, in the Central Highlands of Vietnam, using an integrated approach based on morphological, categorical (color pattern), and mitochondrial NADH dehydrogenase subunit 2 gene (ND2) and its flanking tRNAs data. Phylogenetic analyses recovered Dixonius fulbrighti sp. nov. as closely related to D. gialaiensis from Gia Lai Province and part of a clade that includes D. minhlei, D. siamensis, and D. somchanhae. Multivariate (PCA, DAPC, and MFA) and univariate (ANOVA) analyses of 15 meristic (scale counts), six morphometric (mensural), and five categorical (color pattern and morphology) characters from 44 specimens of all eight species of Dixonius from Vietnam, Laos, and Cambodia clearly demonstrated that Dixonius fulbrighti sp. nov. is statistically different and diagnostically distinct from all closely related species of Dixonius. This new species discovery highlights the underestimated gecko diversity and the importance of continued fieldwork in the Central Highlands of Vietnam.

An integrative analysis recovered a new species of the Hemiphyllodactylus typus group from a karst formation in Lung Cu Commune, Dong Van District, Ha Giang Province, northeastern Vietnam. Hemiphyllodactylus lungcuensis sp. nov. is embedded within clade 6 of the typus group, bearing an uncorrected pairwise sequence divergence of 4.6–20.2% from all other species based on a 1,038 base pair segment of the mitochondrial NADH dehydrogenase subunit 2 gene (ND2). It is diagnosable from other species in clade 6 by statistically significant mean differences in normalized morphometric, meristic, and categorical characters. A multiple factor analysis using the three aforementioned character types recovered its unique, non-overlapping placement in morphospace as statistically significantly different from that of all other species in clade 6. The description of this new Hemiphyllodactylus species contributes to a growing body of literature underscoring the high degree of herpetological diversity and endemism in karst landscapes in Vietnam as well as in the genus Hemiphyllodactylus.

Integrated analyses using maximum likelihood (ML), Bayesian inference (BI), principal component analysis (PCA), discriminate analysis of principal components (DAPC), multiple factor analysis (MFA), and analysis of variance (ANOVA) recovered two new diagnosable species of gekkonid lizards in the genus Dixonius, one from the Central Highlands, Gia Lai Province, Vietnam and another from the Vientiane Province, Laos. Phylogenetic analyses based on the mitochondrial NADH dehydrogenase subunit 2 gene (ND2) and adjacent tRNAs showed that Dixonius gialaiensis sp. nov. is the sister species of D. minhlei from Dong Nai Province, Vietnam and is nested within a clade that also includes the sister species D. siamensis and D. somchanhae. Dixonius muangfuangensis sp. nov. is the sister species to D. lao from Khammouane Province, Laos and is embedded in a clade with D. vietnamensis, D. taoi, and undescribed species from Thailand. Multivariate (PCA, DAPC, and MFA) and univariate (ANOVA) analyses using combinations of 15 meristic (scale counts), six morphometric (measurements), and five categorical (color pattern and morphology) characters from 44 specimens encompassing all eight species of Dixonius from Vietnam and Laos clearly illustrate Dixonius gialaiensis sp. nov. and Dixonius muangfuangensis sp. nov. are statistically different and discretely diagnosable from all closely related species of Dixonius. These integrative analyses also highlight additional taxonomic issues that remain unresolved within Dixonius and the need for additional studies. The discovery of these new species further emphasizes the underappreciated herpetological diversity of the genus Dixonius and illustrates the continued need for field work in these regions.

Gia Lai bent-toed gecko (Cyrtodactylus gialaiensis) was firstly described in 2017, and is an endemic species with very restricted distributional range, estimated to be less than 10 km2 in coffee plantation in Gia Lai province, Central Highland of Vietnam. This species is listed as Critically Endangered (CR) in the IUCN Red List. To date, the natural history of this species is totally unknown. In this paper, we provide the first-of-ever natural history data on this highly threatened gecko species, with emphasis on morphometrics, habitat preferences, thermal ecology, and activity patterns. In 23 days of surveys, we captured 42 C. gialaiensis individuals and recaptured 4 of them. Sex ratio was not skewed from equality and juveniles accounted for 23.8% of the observed individuals. The two sexes did not differ in terms of mean Snout-to-Vent Length, Tail Length and weight, but the adult females had longer head than adult males. Geckos were observed at a mean substratum temperature of 24.2±1°C (n=14), and exhibited a mean body temperature of 29.5±2.5°C (n=14). There was no significant correlation between substratum and body temperatures. Body temperatures were significantly higher than substratum temperatures. The study species exhibited a clearly nocturnal above-ground activity, with main peak occurring between 20:00-21:30 h.

Climate change is one of the most serious threats to the world's biodiversity. Reptiles with limited dispersal capacities, small geographic ranges, or specialised habitats are considered to be especially vulnerable. In this study, we applied the Maximum Entropy algorithm to predict the current and future suitable habitats of a range-restricted species group (Cyrtodactylus chauquangensis) in Vietnam. The models show that the current suitable habitat of C. chauquangensis species group mainly covers areas in Ninh Binh, Thanh Hoa, and a part of Nghe An provinces, Vietnam, covering approximately 83,521.53 km2. The models also indicate Karst Distance, Mean Diurnal Range, and Precipitation of Driest Month as the top three important variables in generating the potential distribution of C. chauquangensis species group. Additionally, we also assessed the impact of climate change on the future suitable habitat of the group under different scenarios. Under the scenario of climate change RCP 4.5, the potential distribution for the group is predicted to decrease significantly, with an average of 59.74% and 65.74% in 2050 and 2070, respectively. For RCP 8.5, the average loss area due to climate change is around 64.18% and 71.44% in 2050 and 2070, respectively. Based on our predictions, suitable habitats in Ninh Binh, Thanh Hoa, and Nghe An provinces could be potential refugia of the group under the impact of climate change. We strongly suggest that these areas be highly prioritised for in-situ conservation measures to safeguard species of the C. chauquangensis group in Vietnam. [ABSTRACT FROM AUTHOR]