Thursday, December 25, 2025

[Herpetology • 2025] Hebius vogeli • Taxonomic Reassessment of Hebius optatus (Hu & Zhao, 1966) (Squamata: Natricidae), with the Description of a New Species from Vietnam and China


Hebius vogeli
Nguyen, Li, Huang, Han, Nguyen, Poyarkov, David & Ren, 2025


Abstract
A comprehensive taxonomic reassessment of the Hebius optatus species complex, integrating molecular data and morphological data, has led to the recognition and description of a previously overlooked species from northern Vietnam and the Guangxi Zhuang Autonomous Region, China, herein described as Hebius vogeli sp. nov. Phylogenetic analyses reveal that Hebius vogeli sp. nov. is closely related to H. sauteri and H. optatus sensu stricto. Uncorrected p-distances based on cytochrome b sequences indicate a divergence of 10.74%–11.73% between Hebius vogeli sp. nov. and H. optatus. The new species differs from H. optatus by a combination of characters, including a higher number of subcaudal scales, a greater total number of ventral and subcaudal scales, and distinct ventral coloration. Hebius vogeli sp. nov. appears to be geographically restricted to northern Vietnam and the adjacent region of Guangxi Zhuang Autonomous Region, China, making its distribution allopatric from that of H. optatus. The Pearl River is hypothesized to serve as a biogeographic barrier separating the two taxa. Accordingly, we recommend the exclusion of H. optatus from the herpetofauna of Vietnam. Based on IUCN Red List criteria, we propose that Hebius vogeli sp. nov. be assessed as Least Concern (LC). Our results emphasize both the underestimated diversity within Hebius and the need for continued integrative taxonomic efforts, particularly in the Vietnam-China borderlands, where cryptic diversity remains largely unexplored.

 Keywords: Asia, cytochrome b, Hebius vogeli sp. nov., morphology, Pearl River, taxonomy

Photographs in life of Hebius vogeli sp. nov. in Vietnam:
(A–C) MNHN 1997.3305 (paratype, adult male) from Tam Dao NP, Phu Tho;
(D–H) uncollected specimen (adult, sex unknown) from Cuc Phuong NP, Ninh Binh (iNaturalist observation 182072957); (I) another uncollected specimen (adult, sex unknown) from Cuc Phuong NP, Ninh Binh.
Photographs by G. VOGEL (A–C), M. LUCASSEN (D–H), and J. HAUSER (I).

 Hebius vogeli sp. nov. 


Tan Van NGUYEN, Maoliang LI, Junjie HUANG, Buying HAN, Duc Trong NGUYEN, Nikolay A. POYARKOV, Patrick DAVID and Jinlong REN. 2025. Taxonomic Reassessment of Hebius optatus (Hu & Zhao, 1966) (Squamata: Natricidae), with the Description of a New Species from Vietnam and China. Asian Herpetological Research. 16(4); 377 - 391. DOI: doi.org/10.3724/ahr.2095-0357.2025.0026 [Dec 5, 2025]
https://cstr.cn/32242.14.ahr.2095-0357.2025.0026