Based on molecular evidence and morphological data, we describe a new species Raorchestes yadongensis sp. nov. from Yadong County, Xizang Autonomous Region, China. The new species can be distinguished based on a combination of the following characters: (1) small body size, SVL 17.8–24.1 mm in adult males; (2) head wider than long; (3) eye diameter about three times as much as tympanum diameter; (4) tympanum distinct; (5) fingers with rudimentary webbing and narrow lateral dermal fringes; relative finger lengths I < II < IV < III; number of subarticular tubercles in fingers 1, 1, 2, 1; (6) toes with rudimentary webbing and narrow lateral dermal fringes; relative toe lengths I < II < III < V < IV; number of subarticular tubercles in toes 1, 1, 2, 3, 2; inner metatarsal tubercle distinct, outer metatarsal tubercle absent; (7) tips of fingers and toes present discs, and discs pale brown or yellow in life; (8) tibiotarsal articulation reaching the tip of snout when adpressed; (9) milky nuptial pad present on the dorsal surface of first finger; (10) dorsal surface light brown with white warts, ventral surface with irregular white patches. The new species is currently known in Yadong County, Xizang, China, but may also occur in neighboring Bhutan and India. A key to Chinese species of the genus Raorchestes is also provided.

A new species of the xenodermid snake genus Achalinus Peters, 1869 is described from Fujian Province, China, based on six specimens. Bayesian inference and maximum likelihood analyses based on a mitochondrial DNA fragment (CO1) indicated the new taxon is different from its congeners (p–distance ≥ 18.5%). Morphologically, the new species can be diagnosed from the other species by a combination of following characters: (1) dorsal scales 23 rows throughout, strongly keeled, the most outer rows on both sides also keeled and slightly enlarged; (2) tail relatively longer, TaL/TL ratio 0.26–0.29 in males, 0.21–0.22 in females; (3) maxillary teeth 30–33; (4) length of suture between internasals significantly longer than that between prefrontals; (5) nasal divided into two sections by nasal cleft; (6) a single loreal; (7) SPO 1, seldom 2; (8) SPL 6, the fourth and fifth contacting eye; (9) IFL5, rarely 6, the first three touching the first pair of chin shields; (10) TMP 7–9, arranged in three rows; (11) VS 142–149 in males, VS 152–154 in females; (12) SC 74–81 in males, SC 63–65 in females, arranged in a single row; (13) cloacal entire; (14) greyish brown above, pale yellow beneath; (15) dorsum with an indistinct longitudinal vertebral stripe. The description of the new species brings the total species of Achalinus to 19.

Jiuzhaigou National Nature Reserve (JNNR) is a renowned World Biosphere Reserve and UNESCO-designated World Nature Heritage Site. The age structure and body size of a population are crucial for assessing the quality of habitats in which a population lives and are essential for the vertebrate conservation and management, especially for amphibians. Unfortunately, information about the life history traits of amphibians is currently unavailable in JNNR. Herein, we first estimated the age structure and body size of Rana kukunoris, which is endemic to the Eastern Qinghai-Xizang Plateau. Then, we compared our data with 28 reported populations along an elevation gradient (1797–3450 m) and investigated how life history traits respond to climatic variations. Our results indicated the following: (1) For individuals from JNNR, the maximum longevity is 8 years, age at sexual maturity (ASM) is 2 years, suggesting a favorable ecological environment in JNNR. Notably, females are significantly larger than males due to the age factor. (2) The average age and ASM show a positive correlation with elevation. However, when the elevation exceeds 3000 m, the average SVL initially increases and then decreases due to the harsh environmental conditions at higher elevation. (3) Temperature and/or UV-B have a significant impact on the average age, ASM, and average SVL variations of R. kukunoris, suggesting adaptive potential of this species via life history variations in light of environmental changes. These accounts provide antecedent information about the life history traits of amphibians in JNNR, and provide insights into the driving factors of the life history variations of the plateau brown frog.

The genus Scincella Mittleman, 1950 of the family Scincidae currently includes 50 species. However, due to challenges in sample collection, the taxonomy and phylogeny of this genus remain poorly resolved. This study conducted a taxonomic study of the genus Scincella based on three mitochondrial gene fragments (12S, 16S, COI) combined with morphological comparisons. The results indicated the specimens collected in Heishui County, Sichuan Province, China, represented a previously undescribed species. This new taxon is formally described as Scincella heishuiensis sp. nov. Phylogenetically, the new species is most closely related to S. wangyuezhaoi, which is another species recently described in Wenchuan County, Aba Prefecture, Sichuan Province. As a new species, the uncorrected genetic distance between this new species and its closest relative within the genus, as calculated based on 16S rRNA, is 5.45%. The new species can be distinguished from other closely related species by the following morphological characters: (1) 4 dorsal scale rows between dorsolateral stripes; (2) 5–7 superciliary; (3) 28 midbody scale-rows; (4) 24–25 gulars; (5) during the breeding season, the ventral scales and preanal exhibit a reddish-brown color; and (6) a black lateral stripe extends from behind the eye to the posterior third of the tail near the cloaca. In the phylogenetic analysis, the new species and S. wangyuezhaoi form an independent lineage, distinctly separate from all other taxa included in the study. The new species has currently been recorded and discovered in Heishui County in Sichuan Province, China. This description thus increases the number of members in the genus Scincella in China to 17 species.

Skeletons serve as the body’s fundamental structure and perform multiple vital functions, and thus even subtle modifications can lead to functional changes. However, studies on sexual shape dimorphism in the appendicular skeletons of anurans remain scarce, especially for fossorial species. Herein, we investigated the sexual differences in the external morphology and internal skeletal shape of girdles and limbs of fossorial Kaloula rugifera during the breeding season. The results reveal the following: (1) Males exhibit significantly longer forelimbs and hindlimbs, suggesting advantages in male—male competition and amplexus. (2) Males possess more curved and dilated coracoids and broader pubis-ischium regions, which may enhance forelimb contraction efficiency and hindlimb locomotor performance. (3) Males feature a more developed crista ventralis, likely enhancing forelimb flexion for tightly grasping females during mating. In contrast, females display a torsioned femur and robust hindlimb morphology, suggesting adaptations for digging and load-bearing. These findings provide insights into how anurans optimize reproductive fitness and ecological adaptations through morphological specialization. To our knowledge, this study presents the first examination of sexual shape dimorphism in anuran appendicular skeletons utilizing three-dimensional geometric morphometrics.

Bufotes taxkorensis and B. zamdaensis are toads endemic to China. Both species inhabit high-elevation and saline environments, and so provide a unique opportunity to investigate the adaptive responses of amphibians to extreme habitats. In the present study, we first observed and measured the histological structures of their skin and kidney in Bufotes taxkorensis and B. zamdaensis. We then compared these results with similar findings for the low-elevation seawater dweller Fejervarya cancrivora and, finally, contrasted them with available data on species living in diverse habitats. Our results revealed the following adaptations: (1) In the Bufotes species, the epidermis and dermis both contain capillary vessels, facilitating blood-gas exchange and promoting adaptation to high-elevation hypoxia. The thick pigment layers present in the ventral skin of B. taxkorensis also help in adaptation to lower temperatures. In addition, the relative epidermis thickness of the dorsal and ventral skin is significantly greater in Bufotes species than in F. cancrivora, indicating adaptation to a terrestrial habitat. Comparing the terrestrial and semiaquatic species, we found that total dorsal and ventral thicknesses are both is significantly greater in terrestrial than in semiaquatic species, helping to reduce water evaporation and damage from crawling, and thus promoting adaptation to terrestrial life. (2) The relative kidney filtration area of the Bufotes species is not significantly different from that of F. cancrivora, but accounts for only half that of terrestrial Bufo species. This lower total relative filtration area prevents excessive urea from being filtered out, avoiding excessive loss of body water and promoting adaptation to saline conditions. At the same time, the relative diameter of the proximal segment of Bufotes species was found to be similar to that of the semiaquatic F. cancrivora, facilitating the resorption of water and ions to increase plasma osmolality and promoting adaptation to saline environments. The findings of the present study offer insights into the adaptive mechanisms of amphibians in extreme environments and different habitats.