Integrative taxonomy reveals three new taxa within the Tylototriton asperrimus complex (Caudata, Salamandridae) from Vietnam

A new skink of the genus Scincella Mittleman, 1950 (Squamata, Scincidae) from Son La Province, northwestern Vietnam

A new species of the genus Scincella Mittleman, 1950 is described from northern Vietnam based on morphological and molecular evidence. Scincellatruongi sp. nov. is characterized by a combination of the following characters: size medium (SVL up to 59.4 mm); primary temporals 2; external ear opening without lobules; loreals two; supralabials seven or eight; infralabials six or seven; nuchals in three pairs; midbody scales in 28 rows; dorsal scales smooth, in six rows across the back; paravertebral scales 60-67, not widened; ventral scales in 60-70 rows; ten smooth lamellae beneath finger IV and 13-15 beneath toe IV; toes not reaching to fingers when limbs adpressed along body; dorsal surface of body and tail bronze brown with few black spots, a dark stripe running from nostril to eye and extending from posterior corner of eye along upper part of flank to the middle of the tail. In the phylogenetic analyses, the new species is recovered as an independent lineage with no clear sister taxon and at least 17.3% genetic divergence from other species in the genus based on a fragment of the mitochondrial COI gene.

Predicting genetic biodiversity in salamanders using geographic, climatic, and life history traits

The geographic distribution of genetic variation within a species reveals information about its evolutionary history, including responses to historical climate change and dispersal ability across various habitat types. We combine genetic data from salamander species with geographic, climatic, and life history data collected from open-source online repositories to develop a machine learning model designed to identify the traits that are most predictive of unrecognized genetic lineages. We find evidence of hidden diversity distributed throughout the clade Caudata that is largely the result of variation in climatic variables. We highlight some of the difficulties in using machine-learning models on open-source data that are often messy and potentially taxonomically and geographically biased.

First report on population status and potential distribution of Tylototritonsparreboomi Bernardes, Le, Nguyen, Pham, Pham, Nguyen, Rödder, Bonkowski & Ziegler, 2020 (Amphibia, Salamandridae) in Vietnam

The Sparreboom's Crocodile Newt (Tylototritonsparreboomi) is a recently discovered species of crocodile newts from Vietnam and it is currently known only from Sin Ho District in Lai Chau Province. Due to the limited information available on its population status and distribution, the species has been classified as Data Deficient in the IUCN Red List. As a result of our field surveys in 2021 and 2022 in north-western Vietnam, novel data on distribution and population status of and threats to this poorly-known species were collected. We combined the newly-discovered locations with previous occurrence records and used the data as input for modelling the potential distribution of the Sparreboom's Crocodile Newt. The results showed that the Sparreboom's Crocodile Newt's potential distribution encompasses areas in Lai Chau, Dien Bien and Son La Provinces, Vietnam, as well as a section in Jinping County, Yunnan Province, China. Based on the findings, we suggest that protected areas in the eastern side of Hoang Lien Mountain Range, such as Che Tao, Muong La, Hoang Lien - Van Ban and Bat Xat Nature Reserves and Hoang Lien National Park in Vietnam and Jinping Feishuling Nature Reserve in China be priority sites for the species conservation. Future research and conservation initiatives should prioritise efforts in such areas in an effort to find and protect new populations of the newt.

Southbound - the southernmost record of Tylototriton (Amphibia, Caudata, Salamandridae) from the Central Highlands of Vietnam represents a new species

A new species of the genus Tylototriton is described from Ngoc Linh Mountain, Kon Tum Province, in the Central Highlands of Vietnam based on integrative taxonomy, namely by combining molecular and morphological evidence. Tylototritonngoclinhensissp. nov. differs from all other congeners based on morphological data, allopatric distribution, and molecular divergence. In terms of genetic divergence, Tylototritonngoclinhensissp. nov. distinctly differs from the sister species T.panhai (6.77%) and from T.ngarsuensis (12.36%) based on the mitochondrial NADH dehydrogenase subunit 2 (ND2) gene. Tylototritonngoclinhensissp. nov. is a moderate sized and robust salamander species with large cephalic edges, parotoids, and vertebral ridge orange in coloration. The new taxon differs from its congeners by a combination of the following morphological characteristics: size medium (SVL 60.8-66.5 mm, TL 57.6-61.8 mm in males, and SVL 72.5-75.6 mm, TL 62.9-67.9 mm in females); head longer than wide; parotoids very prominent and enlarged, projecting backwards; tail length shorter than snout-vent length; vertebral ridge large, high and glandular in appearance; 14 large and distinct dorsolateral glandular warts; gular fold present; tips of fore and hind limbs overlapping when adpressed along the body; tips of fingers reaching between eye and nostril when foreleg is laid forward; dorsal surface and lateral sides of the head, upper and lower lips, dorsolateral glandular warts, vertebral ridge, the peripheral area of the cloaca and the ventral edge of the tail orange in coloration; the presence of a distinct black line extending from the posterior end of the eye towards the shoulder. Tylototritonngoclinhensissp. nov. is restricted to evergreen montane forests near water bodies on Ngoc Linh Mountain. We suggest that the new species should be classified as Endangered (EN) in the IUCN Red List. This new important discovery represents the eighth Tylototriton taxon described from Vietnam, and at the same time constitutes the southernmost distributional record for the whole genus in Asia.

Assessment of the threat status of the amphibians in Vietnam - Implementation of the One Plan Approach

The current decline in global biodiversity is most evident in amphibians with 41% percent of all species worldwide classified as threatened with extinction. Hence, a major challenge in amphibian conservation is the high number of threatened species, leading to a common approach of identifying priority species and regions for conservation efforts. As a part of one of 36 globally designated biodiversity hotspots, Vietnam is considered to be of particular importance for conservation action. To improve amphibian conservation in Vietnam, this study provides an updated species list and assesses their threat status by compiling data from a variety of sources. Furthermore, a Zoological Information Management System (ZIMS) analysis was conducted to determine the representation of extant amphibians from Vietnam in zoos worldwide. The batrachofauna of Vietnam is characterized by a high level of species richness and local endemism as well as a high rate of new discoveries, with more than half of the endemic species reported exclusively from their type locality, making them especially vulnerable to extinction. Up to 18% of all amphibians extant in Vietnam and 28% of endemic species are classified as threatened with extinction by the IUCN. In many cases, the IUCN Red List status is either missing or outdated, highlighting the urgent need of action. Around 14% of endemic amphibian species have been recorded exclusively from unprotected areas, suggesting prioritization for further research and conservation measures. The continuing decline in many species remains an unresolved problem. As a guide for future research and conservation measures, a list of the top 57 species was compiled. In addition, according to the ZIMS analysis, only 8% of threatened and 3% of endemic amphibian taxa from Vietnam are currently kept in zoos worldwide, and a richness analysis revealed that the highest density of husbandries is found in Europe and North America. To achieve maximum outcome for the conservation of threatened species, this study recommends a general shift by zoos towards maintaining species in greater need of captive assurance populations and breeding programs to support integrative strategies that combine in situ and ex situ conservation efforts following the IUCN’s One Plan Approach.

A new species of the genus Tylototriton (Urodela, Salamandridae) from western Thailand

We describe a new species of the newt genus Tylototriton from Umphang Wildlife Sanctuary, Tak Province, western Thailand based on molecular and morphological evidence and named here as Tylototritonumphangensissp. nov. The new species is assigned to the subgenus Tylototriton and differs from other species in having dark-brown to blackish-brown body and limbs, truncate snout, prominent antero-medial ends of the expansion of the dentary bones, laterally protruding quadrate regions, indistinct and small rib nodules, a well-segmented vertebral ridge, and rough dorsolateral bony ridges, which are steeper anterior, and curved medially at the posterior ends. The molecular data show that Tylototritonumphangensissp. nov. differs from T.uyenoi sensu stricto by a 5% genetic sequence divergence of the mitochondrial NADH dehydrogenase subunit 2 region gene. The new species and T.uyenoi are both endemic to Thailand, distributed along the Northwest Thai (Dawna) Uplands of Indochina. To clarify the species boundary between Tylototritonumphangensissp. nov. and T.uyenoi, additional field research is needed in adjacent areas. Tylototritonumphangensissp. nov. is restricted to evergreen hill forests in Umphang Wildlife Sanctuary. We suggest that the new species should be classified as Endangered (EN) in the IUCN Red List.

A new species of the genus Tylototriton (Caudata, Salamandridae) from Guangdong, southern China, with discussion on the subgenera and species groups within the genus

In this work, a new species of the genus Tylototriton is described from Guangdong, southern China. Tylototriton sini sp. nov. was recorded as T. asperrimus for decades, and was indicated to represent an independent lineage based on recent molecular phylogenetic analyses. After detailed molecular analysis and morphological comparisons, Tylototriton sini sp. nov. is recognized as a distinct species which can be clearly distinguished from all known congeners by a combination of morphological characteristics and the significant divergence in the mitochondrial gene. Because the genus Tylototriton is of high conservation concern and all formally described members are protected by law, we also provide first data on the conservation status and recommendations for IUCN categorization for Tylototriton sini sp. nov. A suggestion on the species groups division of the genus Tylototriton is also provided based on their morphological differences and phylogenetic relationships.