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Issue: Vol. 5845 No. 3: 7 Jul. 2026
Type: Article
Published: 2026-07-07
DOI: 10.11646/zootaxa.5845.3.5
Page range: 523-544
Abstract views: 58
PDF downloaded: 3

Redescription and range extension of Pareas dulongjiangensis Liu, Yang, Rao, Guo & Rao, 2023 (Squamata: Pareidae)

State Key Laboratory of Plateau Ecology and Agriculture; Qinghai University; Xining 810016; Qinghai; China
The Anhui Provincial Key Laboratory of Biodiversity Conservation and Ecological Security in the Yangtze River Basin; College of Life Sciences; Anhui Normal University; Wuhu 241000; Anhui; China
The School of Medicine & Pharmacy; Duy Tan University; Da Nang; 550000; Vietnam; Center for Entomology & Parasitology Research; Duy Tan University; Da Nang; 550000; Vietnam
State Key Laboratory of Plateau Ecology and Agriculture; Qinghai University; Xining 810016; Qinghai; China
Society for Southeast Asian Herpetology; D-69115 Heidelberg; Baden-Württemberg; Germany
State Key Laboratory of Plateau Ecology and Agriculture; Qinghai University; Xining 810016; Qinghai; China
Department of Vertebrate Zoology; Lomonosov Moscow State University; Leninskiye Gory; GSP-1; Moscow 119991; Russia
State Key Laboratory of Plateau Ecology and Agriculture; Qinghai University; Xining 810016; Qinghai; China
Reptilia morphology Myanmar new record phylogeny taxonomy Pareas hamptoni species group

Abstract

The Dulongjiang slug-eating snake Pareas dulongjiangensis was described based on a single preserved female specimen collected in Gongshan County, Nujiang Prefecture, Yunnan Province, China. Consequently, important aspects of its morphology, live coloration, sexual dimorphism, and geographic distribution have remained poorly understood. In this study, we report four additional specimens collected from Dulongjiang Township, Yunnan Province, China. Molecular phylogenetic analyses based on mitochondrial DNA confirm that these specimens cluster with P. dulongjiangensis, showing minimal genetic divergence from the type specimen (uncorrected p-distance of 0.0–0.9% in the Cyt b gene). The newly available material allow us to refine the diagnosis of the species, provide a broader redescription, and document intraspecific variation, including previously unknown male specimens and hemipenial morphology. We also present the first photographs of the species in life. Re-examination of a specimen from Hkakabo Razi National Park, Kachin State, northern Myanmar, previously referred to as Pareas sp. by Vogel et al. (2021), indicates that it represents P. dulongjiangensis, thereby extending the known distribution of the species to Myanmar. In addition, we clarify an important diagnostic character by demonstrating that the species possesses a single prefrontal scale, correcting earlier reports of paired prefrontals. Our results highlight the importance of adequate sampling in taxonomic studies, as reliance on a single specimen may lead to misinterpretation of intraspecific variation. Further integrative studies with broader sampling are required to better resolve morphological variation and species boundaries within the Pareas hamptoni species group.

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How to Cite

Xu, Y., Zhang, T., Nguyen, T.V., Sun, F., Vogel, G., Deng, J., Poyarkov, N.A. & Peng, L. (2026) Redescription and range extension of Pareas dulongjiangensis Liu, Yang, Rao, Guo & Rao, 2023 (Squamata: Pareidae). Zootaxa, 5845 (3), 523–544. https://doi.org/10.11646/zootaxa.5845.3.5