We describe a new species of the genus Achalinus Peters, 1869 from Daming Mountain, Shanglin County, Nanning City, Guangxi Zhuang Autonomous Region, China, based on a single adult male specimen. It can be distinguished from all the other species in Achalinus by a combination of the following morphological characters: (1) a bright yellow collar around the neck, extending forward to the ventral of the head; (2) tail length comparatively long, TaL/Tol ratio 0.25; (3) DSR 23-23-23, moderately keeled; (4) VS 3+162; (5) SC 74, unpaired; (6) cloacal plate entire; (7) SPL 6, the fourth and fifth in contact with the eye; (8) IFL 6, the first three touching the first pair of chin shields; (9) a single loreal; (10) length of suture between internasal significantly longer than that between prefrontal, LSBI/LSBP ratio 1.34; (11) two pairs of chin shields; (12) longitudinal vertebral line absent. In addition, the uncorrected p-distances between the new species and other known congeners ranged from 6.3% to 25.4% for the cytochrome c oxidase subunit 1 (CO1). With the addition of the new species the total number of described Achalinus species is increased to 23 of which 17 are found in China.
A new species, Achalinus sheni sp. nov., from central Hunan Province is described, based on the results of molecular systematics and morphological characters according to five specimens. Our molecular phylogeny inferred from the mitochondrial CO1 gene fragment revealed that this new species is most closely related to A. yunkaiensis, but a considerable amount of genetic divergence exists between them (p-distance ranging from 5.8% to 6.4%) and much distinct genetic divergence exists compared with other known Achalinus species (p-distance ranging from 10.4% to 15.8%), supporting its validity. Morphologically, it can be distinguished from its congeners by: (1) dorsal scales strongly keeled, 23 rows throughout the body, the outmost row smooth and significantly enlarged; (2) tail relatively short, TaL/TL 0.183 ~ 0.224; (3) the suture between internasals subequal to the suture between prefrontals; (4) loreal one, subrectangular, LorH/LorL 0.53 ~ 0.57; (5) ventrals 161–170, anal entire, subcaudals 55–61, not paired; (6) the length of supraocular equal to or longer than the length of upper anterior temporal; and (7) vertebral line inconspicuous and subcaudal streak absent. Currently, 27 species of Achalinus are known in the world, amongst which 20 species are distributed in China. Moreover, a key to species of the genus Achalinus is provided in this study.
A new species of the genus Hebius Thompson, 1913 is described from Yingjiang County, Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province, China, based on molecular and morphological evidence. It can be distinguished from its congeners by the following set of characters: (1) dorsal scale rows 19–17–17, feebly keeled; (2) ventrals 146–151; (3) nasal complete, nostril in the middle of the nasal; (4) supralabials 9, the fourth to sixth in contact with the eye; (5) infralabials 10–11, the first 5 touching the first pair of chin shields; (6) preoculars 2; (7) postoculars 3; (8) temporals 3, arranged in two rows (1+2); (9) maxillary teeth 31, the last 4 slightly enlarged, without diastema; (10) tail comparatively long, TAL/TL ratio 0.334 in the male; (11) dorsolateral series of irregular orange or ochre yellow blotches, extending from the neck to the posterior part of the tail; and (12) venter pale orange, tips of ventrals with subrectangular black blotches. All Hebius specimens were strongly recovered as monophyletic, in which Hebius taronensis (Smith, 1940) and Hebius venningi (Wall, 1910) were monophyletic as sister to the Yingjiang County specimens. According to the p‐distance of cytochrome b, the new species differs from its congeners by 9.7–15.4%.
A new species of the genus Hebius Thompson, 1913 is described from Youjiang District, Baise City, Guangxi Zhuang Autonomous Region, China, based on a single adult female specimen. It can be distinguished from its congeners by the following combination of characters: (1) dorsal scale rows 19-17-17, feebly keeled except the outermost row; (2) tail length comparatively long, TAL/TL ratio 0.30 in females; (3) ventrals 160 (+ 3 preventrals); (4) subcaudals 112; (5) supralabials 9, the fourth to sixth in contact with the eye; (6) infralabials 10, the first 5 touching the first pair of chin shields; (7) preocular 1; (8) postoculars 2; (9) temporals 4, arranged in three rows (1+1+2); (10) maxillary teeth 30, the last 3 enlarged, without diastem; (11) postocular streak presence; (12) background color of dorsal brownish black, a conspicuous, uniform, continuous beige stripe extending from behind the eye to the end of the tail; (13) anterior venter creamish-yellow, gradually fades to the rear, with irregular black blotches in the middle and outer quarter of ventrals, the posterior part almost completely black. The discovery of the new species increases the number of species in the genus Hebius to 51.
We described a new species of genus Pareas from Baise City, Guangxi Zhuang Autonomous Region, China, based on morphological and molecular evidence. Pareas baiseensis sp. nov. is distinguished from its congeners by the combination of (1) Yellowish-brown body colouration; (2) Frontal subhexagonal to diamond-shaped with its lateral sides converging posteriorly; (3) The anterior pair of chin shields is longer than it is broad; (4) Loreal not in contact with the eye, prefrontal in contact with the eye, two or three suboculars; (5) Rows of 15–15–15 dorsal scales, five rows of mid-dorsal scales keeled at the middle of the body, one vertebral scale row enlarged; (6) 187–191 ventrals, 89–97 subcaudals, all divided, cloacal plate single; (7) Two postocular stripes, the nuchal area forming a dark black four-pointed fork collar with the middle tines shorter than the outside tines. The genetic divergence (uncorrected p-distance) between the new species and other representatives of Pareas ranged from 13.9% to 24.4% for Cytochrome b (Cyt b) and 12.1% to 25.5% for NADH dehydrogenase subunit 4 (ND4). Phylogenetic analyses of mitochondrial DNA gene data recovered the new species from being the sister taxon to (P. boulengeri + P. chinensis) from China.
Albinism is an uncommon phenomenon and inherited condition in animals characterized by a partial or complete lack of melanin. The family Xenodermidae Gray, 1849, is a group of caenophidian snakes widely distributed in South, East, and Southeast Asia, including five recognized genera and 36 species. However, there are currently no reports of albinism in any species in Xenodermidae. Achalinus sheni Ma, Xu, Qi, Wang, Tang, Huang & Jiang, 2023 was first described based on five male specimens from Loudi City and Nanyue District, Hunan Province, China. At the time, there were no descriptions on female individuals. In this study, we report in detail a collected albinistic specimen of A. sheni, which is the first discovery of wild albinism in the family Xenodermidae. We also provide photographs and descriptions of the first three female specimens of A. sheni and extend the diagnosis of this species.