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| Trimeresurus hongheensis Liang, Ding, Wang, Vogel, Shi, Gong, Wu & Chen, 2025 |
Abstract
The genus Trimeresurus currently contains at least 56 recognized species of venomous terrestrial to arboreal species distributed across South and Southeast Asia. We collected several specimens of the subgenus Viridovipera in Yunnan Province, China in recent years. Based on morphological characters and phylogenetic analysis, we confirm that Trimeresurus yunnanensis is distributed in the west of the Honghe River in Yunnan Province and the Trimeresurus species living along the lower reaches of the Honghe River Basin and adjacent areas is an undescribed taxon. The new species Trimeresurus hongheensis sp. nov. can be distinguished from all known congeners by the pairwise genetic divergence in the mitochondrial cytochrome-b (p-distance≥5.0%) and 16S rRNA gene fragment (p-distance≥0.5%), and morphologically by the combination of the following characters: (1) hemipenes short and strongly spinose, with deep bifurcation; (2) a white postocular stripe bordered above and below by red or only a white postocular stripe present in males; postocular stripe white or absent in females; (3) the ventrolateral stripe is red (below) and white (above) in males and white in females; (4) iris brick red or sepia in males; iris yellow or rusty-red in females; (5) VEN 150–165 in males and 157–165 in females; SC 61–76 in males and 56–61 in females; (6) dorsal tail mostly rusty red; (7) 9–12 cephalic scales; (8) 19 or 21 dorsal scale rows at mid-body; (9) first supralabial completely separated from the nasal scale.
Keywords: Mitochondrial DNA, Morphology, Honghe River, Phylogenetics, Trimeresurus hongheensis sp. nov., Viridovipera
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| Trimeresurus hongheensis sp. nov. in Yunnan, China, males (Left) and females (Right) in life A: Mingjiu, Mengzi (Holotype GXNU251201). B: Mingjiu, Mengzi (GXNU251218). C: Yuanjiang (Paratype GXNU251204). D: Yuanjiang (Paratype GXNU251205). E: Mt. Dawei, Pingbian County, Yunnan (Paratype GXNU251219). F: Yuanjiang (Paratype GXNU251203). Photos by Li Ding. |
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| Holotype (adult male GXNU251201) of Trimeresurus hongheensis sp. nov. A: Dorsal view of head; B: Ventral view of head; C: Lateral view of head; D: Lateral view of middle body; E: Dorsal view of the specimen; F: Ventral view of the specimen. Photos by Sheng-Chao Shi. Scale bars: 10 mm (A, B, C, D); 3 cm (E, F). |
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| Comparison of head shape and coloration between males and females in Trimeresurus hongheensis sp. nov. Left, dorsal view of head; right, lateral view of head. A & B: Specimen GXNU251201 (holotype, male); C & D: Specimen GXNU251219 (paratype, male); E & F: Specimen GXNU251205 (paratype, female); G & H: GXNU251218 (female). A & C: Different head shape in males (more elongated skull vs short skull); B & D: Different iris color in males (brick red vs sepia); E & G: Different head shape in females (more elongated skull vs short skull); F & H: Different postocular stripe (present vs absent) and different iris color (yellow vs rusty-red) in females. Photos by Sheng-Chao Shi. |
Trimeresurus hongheensis sp. nov.
Etymology: The new species name “hongheensis” refers to its type locality, the area around the Honghe River Basin, which is a boundary of the new species and T. yunnanensis. For common name we suggested as “Honghe green pit-viper” in English and “Hóng hé Zhú Yè Qīng (红河竹叶青)” in Chinese.
Diagnosis: (1) Head and body dorsum dark green, venter yellow green or light green. (2) 80% of the tail is rusty red, gradually fusing backwards, with dark red at the end of the tail. (3) Interstitial skin black. (4) Head dark green above, light yellow or light green below, clearly defined. (5) Iris brick red or sepia in males; iris yellow or rusty-red in females. (6) A white postocular stripe bordered above and below by red or only a white postocular stripe present in males, occupying only about 1–2 rows of scales across; postocular stripe white or absent in females. (7) Vivid, broad, bicolored ventrolateral stripe, red below and white above in males, covering 1–2 scales thick; thin white ventrolateral stripe present on the first row of DSR in females. (8) First supralabials separated from nasals. (9) Internasals separated by 0–2 scale. (10) Supraoculars separated by 9–12 smooth cephalic scales. (11) Head scales feebly keeled; 19 or 21 dorsal scale rows at mid-body, feebly keeled except for the outermost rows; VEN 150–165 in males (n=10), 157–165 in females (n=7); SC 61–76 in males (n=7), 56–61 in females (n=7). (12) Tail length to total length ratio (TaL/TL) 0.172–0.204 in males (n=7), 0.145–0.160 in females (n=7). (13) Hemipenes short and strongly spinose, with deep bifurcation.
Ya-Ting Liang, Li Ding, Xin Wang, Gernot Vogel, Sheng-Chao Shi, Xiong Gong, Zheng-Jun Wu and Ze-Ning Chen. 2025. Integrative Taxonomy identifies A New Species of Trimeresurus Lacépède, 1804 (Reptilia: Serpentes: Viperidae) from Yunnan Province, China. Zoological Research: Diversity and Conservation. 2(3): 182-195. DOI: doi.org/10.24272/j.issn.2097-3772.2025.022
