Wednesday, August 12, 2026

[Herpetology • 2026] Hebius yangi • A New Species of the Hebius atemporalis complex (Serpentes: Natricidae) from southeastern Yunnan, China


Hebius yangi
 Liu, J. Wang, Hou, Deng, Zhang, M. Wang & Rao, 2026

Yang’s Keelback | 杨氏腹链蛇  ||  DOI: doi.org/10.3897/zookeys.1289.189681

Abstract
A new species of the Hebius atemporalis complex is described from Wenshan Prefecture, Yunnan Province, China, based on morphological and molecular evidence. The new species can be distinguished from other species of the complex by the differences in the ratio of tail length to total length, the number of ventral and subcaudal scales, the number of maxillary teeth, and the coloration of the iris and anterior body. Phylogenetically, the new species is separated from other species of the complex by an uncorrected p-distance of 6.0–7.8% in the mitochondrial cytochrome b gene. This study further highlights the cryptic diversity in the H. atemporalis complex and the need to re-examine previous records of H. atemporalis and specimens previously considered H. atemporalis from central-southern China, as well as northeastern Vietnam.

Key words: Complex, cytb, keelback snake, morphology, taxonomy, Wenshan Prefecture

The holotype (KIZ2025058) of Hebius yangi sp. nov. in life.
A. Dorsal view; B. Ventral view.

Close-up views of the head of the holotype (KIZ2025058) of Hebius yangi sp. nov. in life.
A. Dorsal view; B. Ventral view; C. Left view; D. Right view.

Hebius yangi sp. nov.

Diagnosis. Body size relatively small, SVL 237–306 mm; tail moderately long, TaL/TL 0.32–0.33; dorsal scale rows 17-17-17, all keeled except the outermost rows; ventrals 130–131; subcaudals 80–85, paired; supralabials six, third and fourth entering orbit; infralabials seven; maxillary teeth 32–34, gradually enlarged posteriorly; dorsal surface grayish brown to blackish brown with a series of neatly arranged small orange spots on dorsolateral body on each side; ventral surface of head white, scattered with black streaks on scale sutures; iris brownish gray; lip region black and white alternately; neck collar present, discontinuous.

Etymology. The specific epithet is in commemoration of the late renowned Chinese herpetological taxonomist Prof. Dr Datong Yang. We suggest “Yang’s Keelback” as the common English name and “杨氏腹链蛇” as the common Chinese name.


 Shuo Liu, JiShan Wang, Mian Hou, Tao Deng, Chaowu Zhang, Mo Wang and Dingqi Rao. 2026. A New Species of the Hebius atemporalis complex (Squamata, Natricidae) from southeastern Yunnan, China. ZooKeys. 1289: 141-157. DOI: doi.org/10.3897/zookeys.1289.189681 [11-08-2026]