Yayong Wu’s research while affiliated with Yibin University and other places

Habitat quality and availability are crucial for the survival and reproduction of animal species. Intraspecific and seasonal differences in habitat selection reflect adaptations to changing biological requirements and environmental factors. To investigate the effects of season (breeding and non-breeding) and sex on microhabitat selection in snakes, here we employed field surveys to analyze microhabitat selection data for Stejneger’s bamboo pitviper ( Viridovipera stejnegeri ) across different sexes and seasons. Results indicated that although no significant difference was observed between groups, marked differences in certain microhabitat factors were noted. Specifically: (1) Non-breeding season females (NBF) displayed distinct differences in altitude, slope position, distance from roads compared to other groups. (2) Temperature exerted a lesser effect on non-breeding season individuals compared to breeding season individuals. Additionally, distance from roads only significantly impacted breeding season males, not females. (3) Regarding sexual differences, males and females differed in slope position and distance from residential sites, reflecting their distinct ecological requirements. Regarding seasons, differences in habitat selection between breeding and non-breeding seasons were primarily related to temperature, indicating behavioral changes linked to seasons. (4) Non-breeding season females exhibited the narrowest microhabitat niche width and the least microhabitat niche overlap with other groups, potentially due to their pronounced foraging requirements, which compel them to explore limited habitats with higher human disturbance but richer food sources. This study contributes novel insights into the habitat selection behaviors of snakes.

Habitat selection in animals results from a careful balance of individual requirements, environmental conditions, and ecological disturbances. Preferences can vary across sexes and ages due to differences in survival and reproductive priorities. Despite this variability, most studies have traditionally focused on isolated aspects of either sex or age‐related differences in habitat selection, rather than considering a comprehensive range of influencing factors. The mountain dragon lizard (Diploderma splendidum) exemplifies a species adapted to shrub habitats in the dry‐hot river valleys of the lower Jinsha River, Western China, playing a crucial role in regional ecosystem stability. In this study, we examined the influence of 11 ecological factors on habitat selection by male and female D. splendidum across two distinct age classes (adult and juvenile) to explore sex and age‐related disparities. The lizards showed considerable similarity in habitat preferences, but notable differences in their selection of specific ecological factors. Compared to adult females, adult males displayed a preference for higher tree positions, lower light intensity, and moderate vegetation density. Compared to juvenile females, juvenile males favored higher tree positions, low rock formations, and shrubby grassland and forest. Compared to juvenile females, adult females preferred higher tree positions and habitats further from water. Compared to juvenile males, adult males preferred higher tree habitats. Overall, habitat selection complexity in D. splendidum was significantly influenced by sex and age factors. This study contributes to our understanding of how these lizards respond to different physiological structures and resource requirements. These findings enhance current knowledge on reptile habitat selection and provide theoretical insights crucial for ecological restoration and species protection in the hot and dry valley areas of Hengduan Mountain.

Lycodon gammiei (Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of L. gammiei rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that L. gammiei constitutes an independent evolutionary lineage, forming a clade with L. fasciatus (Anderson, 1879), L. gongshan Vogel & Luo, 2011, L. butleri Boulenger, 1900, and L. cavernicolus Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between L. gammiei and its congeners was 10.2%. The discovery of L. gammiei in Medog County, China, signifies an eastward expansion of its known geographical distribution.

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 .

A new species of Xenophrys is described from Yadong County, Tibet Autonomous Region, China based on morphological and molecular evidence. Phylogenetic analyses based on the mitochondrial genes 16S rRNA and COI indicated that this new species represents an independent lineage and the minimum p -distance based on 16S rRNA between this species and its congeners is 4.4%. Additionally, the new species is distinguished from its congeners by a combination of the following morphological characters: (1) small body size, SVL 17.9–22.2 mm in adult males and SVL 23.4 mm in the single adult female; (2) tympanum indistinct, supratympanic fold distinct; (3) canthus rostralis well-developed, snout tip far beyond the margin of the lower lip; (5) pupil vertical; (6) vomerine teeth present, maxillary teeth present; (7) tongue notched posteriorly; (8) supernumerary tubercles absent, subarticular, metacarpal and metatarsal tubercles indistinct; (9) relative finger lengths I < II < IV < III, finger tips rounded, slightly expanded relative to digit widths; (10) toes with narrow lateral fringes and tarsal folds; (11) a dark triangular marking with light edge between eyes, a dark “)(”-shaped marking, with light edge, present on center of dorsum, pectoral glands on sides of the breast.

The elucidation of species diversity and distribution is critical within the fields of evolution, genetics, and conservation. The genus Sibynophis contains rare snakes that have historically received little attention. In this study, we conducted comprehensive sampling and use both mitochondrial and nuclear genetic markers to explore Sibynophis species diversity within China. Our findings revealed that S. c. miyiensis should be considered synonymous with S. c. grahami, and S. c. grahami should be gave a specific rank as S. grahami. In addition, we discovered S. triangularis was new to China and Myanmar. Based on the specimens and molecular phylogeny results, we redefined the species distribution boundaries of each Chinese species.

Illumination of species diversity and their distribution is key to evolution, genetics and conservation. The genus of Sibynophis is a group of rare snakes with less attentions. Based on more extensive sampling, we use both mitochondrial fragments and nuclear gene to explore the species diversity of the species of Sibynophis occurring in China. The results showed that S. c. miyiensis is a synonym of S. c. grahami, and S. c. grahami should be gave a specific rank as S. graham. Sibynophis triangularis was uncovered to be new to China and Myanmar. On basis of our specimens and molecular phylogeny results, the species distribution boundaries of each Chinese species were redefined.

Achalinus yangdatongi Hou, Wang, Guo, Chen, Yuan & Che, 2021 was described based on single specimen. After morphological examination of recently collected specimens from the type locality and close region, several specimens (3 females and 1 male) were identified as this species. Genetic distances (p-distance) calculated from a fragment of the mtDNA gene, cytochrome c oxidase subunit I (COI) were less than 1.8% between the newly collected specimens and the type specimen. Achalinus yangdatongi is redescribed and several of its diagnostics are revised accordingly: dorsal body scales 23 rows throughout; ventrals 155–171; subcaudals 59–76, unpaired; maxillary teeth 24–26.

Lizards exhibit sexual dimorphism in various phenotypic traits and capability performance (e.g. bite force), while the patterns of sexual dimorphism vary among genera and species. The relationship between morphology and function is dynamic, and selective pressures can differentially affect bite performance in different sexes. Here, we analyzed sexual dimorphism in morphological traits and bite force and explored the determinants of bite force in the mountain dragon (Diploderma batangense) from western China. A total of 135 individuals were collected, and nine morphological characteristics and bite force were measured. We found a significant male bias in morphology and bite force performance, with males found to be larger than females in regard to head size, body size, limb length, tail length and bite force, which could be explained by sexual selection. Results also showed that bite force was positively correlated with head size, with the determinant affecting bite force differing between males( mouth length) and females( head width), which may be related to their different roles in reproduction. This study provides a reference for understanding the ecological adaptability of mountain dragons in the field and lays a foundation for revealing the mechanism of bite force variation between the sexes.

Lycodon is a species-rich genus that currently contains 72 named species. Lycodon zayuensis Jiang, Wang, Jin & Che, 2020, was described from Lower Chayu Town, Chayu County, Tibet, China, based on a single female holotype. During our recent field work, three additional specimens, including two females and one male, were collected and identified as L. zayuensis based on morphological comparison and the cytochrome b mitochondrial gene (1049 bp). Here, we provide an expanded description of this recently described species based on all known specimens.