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| Ovophis langbianus Poyarkov, Idiiatullina, Ustinova, Bragin, Le, Pawangkhanant, Pham, Suwannapoom, David, Vogel & Nguyen, 2206 |
Abstract
A new species of the genus Ovophis Burger in Hoge & Romano-Hoge, 1981, is described from the Langbian Plateau, southern Vietnam, based on an integrative taxonomic approach combining morphological and molecular evidence. Ovophis langbianus sp. nov. is distinguished from its congeners by a unique combination of diagnostic morphological characters and by significant genetic divergence in the mitochondrial cytochrome b gene. Phylogenetic analyses recover the new species as the sister lineage of O. tonkinensis (Bourret), from which it differs in body proportions, head morphology, color pattern, and several meristic characters. Multivariate analyses of morphological variation further support the distinctiveness of the new species, with specimens of Ovophis langbianus sp. nov. and O. tonkinensis forming two well-separated groups in morphospace and exhibiting significant differences in centroid positions. The new species is currently known only from montane evergreen forests of the Langbian Plateau at elevations of approximately 800–2,230 m asl. The recognition of Ovophis langbianus sp. nov. further emphasizes the taxonomic complexity of the O. tonkinensis species group and, together with previous molecular evidence for a distinct Cao Bang (Vietnam)-Guangxi (China) lineage, highlights the need for a comprehensive reassessment of species boundaries within the complex.
Key Words: Biogeography, molecular phylogeny, morphology, mtDNA, Ovophis langbianus sp. nov., southern Annamite Mountains, systematics
Ovophis langbianus sp. nov.
Diagnosis. Ovophis langbianus sp. nov. can be distinguished from all other congeners by the following combination of characters: (1) TaL/TL ratio 0.14–0.18 in males and 0.12–0.14 in females; (2) internasals usually in contact, rarely separated by one small scale; (3) second supralabial bordering loreal pit; (4) dorsal scale rows 25 (21, 23, 27)–21 (23, 25)–19 (15, 17); (5) ventrals 129–138; (6) dorsal scales strongly keeled; (7) subcaudals 36–44, all single; (8) fourth supralabial larger than third; (9) dorsal surface of head uniformly ...
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| Ovophis langbianus sp. nov. in life from Langbian Plateau, Vietnam — Lam Dong Province: Bidoup-Nui Ba NP: A. VRTC NAP-18223, adult male, holotype; Di Linh Commune: B. Dorsal view of ZMMU Re-18511, adult male, paratype; C. Head in lateral view of the ZMMU Re-18511; D. ZMMU Re-18512, adult male, paratype; E. Head in lateral view of the ZMMU Re-18512; F, G. Two adult individuals, sex undetermined. Dak Lak Province: — Chu Yang Sin NP: H. ZMMU Re-14068, adult male, paratype; I. Head in dorsal view of the ZMMU Re-14068. Photographs by A.M. Bragin (A), N.A. Poyarkov (B, C, H, I), P. Pawangkhanant (D, E), and H.N.X. Nguyen (F, G). |
Etymology. The specific epithet “langbianus” is a masculine Latin adjective derived from the name of the Langbian Plateau, the broader geographic region containing the type locality and the currently known distribution of the new species. The name highlights the biogeographic isolation of the Langbian Plateau, an important center of montane endemism in Indochina.
We suggest the following common names for the new species: “Langbian Mountain Pitviper” (in English), “Rắn lục núi Langbian” (in Vietnamese), “Лангбианский горный щитомордник” (Langbianskiy gornyi schitomordnik, in Russian), and “Ovophis de Langbian” (in French).
Nikolay A. Poyarkov, Sabira S. Idiiatullina, Darya A. Ustinova, Andrey M. Bragin, Son Xuan Le, Parinya Pawangkhanant, Hieu Minh Pham, Chatmongkon Suwannapoom, Patrick David, Gernot Vogel, Tan Van Nguyen. 2206. A New Species of the Ovophis tonkinensis species complex (Serpentes, Viperidae) from the Langbian Plateau, southern Vietnam. Herpetozoa. 39: 325-342. DOI: doi.org/10.3897/herpetozoa.39.e206094 [25-08-2026]