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| Trimeresurus loong Xu, Deng, Zhang, Nguyen, Poyarkov, Vogel & Peng, in Xu, Deng, Zhang, Nguyen, Weng, Poyarkov, Vogel, Sun, Liao et Peng, 2025. |
Abstract
A new species of the genus Trimeresurus Lacépède is described from Kunming City, Yunnan Province, China, based on an integrative analysis of morphological and molecular data. The new species, Trimeresurus loong sp. nov., is assigned to the subgenus Viridovipera Malhotra & Thorpe and can be distinguished from its congeners by the following combination of characters: the first supralabial completely separated from the nasal scale; a short and spinose hemipenis; moderate adult body size; dorsal scales in 19 (21 or 23)-19-15 rows; 150–151 ventral scales in males, and 157–158 in females; 67–68 subcaudals in males, and 57–64 in females; and distinct body color patterns. Molecular analyses based on the mitochondrial 16S, cyt b, and ND4 gene fragments indicate that Trimeresurus loong sp. nov. is genetically divergent from all currently recognized congeners, showing uncorrected p-distances ranging from 6.7–11.2% in cyt b and 6.1–8.3% in ND4. The discovery of this species brings the total number of recognized Trimeresurus species to 57, including nine recorded from Yunnan Province, further emphasizing the complex topography and exceptional level of endemism.
Key Words: Hemipenis, molecular phylogeny, morphology, taxonomy, Trimeresurus loong sp. nov., Southwestern China, systematics
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| Coloration of the holotype of Trimeresurus loong sp. nov. in life (QHU R2025027, adult male). A. Dorsolateral view; B. Ventral view; C. Dorsal view of the head; D. Lateral view of the head; E. Ventral view of the head; F. Lateral view of the body; G. Ventral view of the body. Photographs by Y.H. Xu. |
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| Coloration of the paratypes of Trimeresurus loong sp. nov. in life. A. Lateral view of the head; B. Dorsolateral view; C. Ventral view. A1–C1. QHU R2025028, adult male; A2–C2. QHU R2025029, subadult male; A3–C3. QHU R2025030, subadult male; A4–C4. QHU R2025031, adult female. Photographs by Y.H. Xu. |
Trimeresurus loong Xu, Deng, Zhang, Nguyen, Poyarkov, Vogel & Peng, sp. nov.
Diagnosis. The new species Trimeresurus loong sp. nov. is distinguished from all of its congeners by a combination of the following morphological characters: (1) first supralabial completely separated from the nasal scale; (2) hemipenis short and spinose, reaching the 10th–11th subcaudal when fully everted; (3) moderate adult body size, with a maximum SVL of 601 mm in males and 657 mm in females; (4) dorsal scales in 19 (21 or 23)–19–15 rows, keeled except for the outermost rows; (5) VS 150–151 in males and 157–158 in females; (6) SC 67–68 in males and 57–64 in females; (7) iris amber and sometimes exhibiting a faint reddish hue in adult males and yellowish in adult females; (8) body uniformly bright grass-green; (9) postocular streak narrow and white, with a few scale margins slightly tinged with yellow or reddish-brown in males, and absent in females; (10) ventrolateral stripe along the first dorsal scale row, variable in coloration in males, occurring in two forms, the first is a narrow white band bordered dorsally by a faint yellowish margin and ventrally by a red line, with a diffuse brownish tinge below the red line; the second is a narrow white band bordered by faint yellowish margins; and in females, the stripe is absent or reduced, and almost entirely white when present; (11) the ventral surfaces pale yellowish white or pale greenish-yellow anteriorly; gradually transitioning to greenish-yellow or light green toward the posterior body; (12) tail distinctly bicolored dorsally, green anteriorly and becoming almost uniformly orange or light orange-red posteriorly.
Etymology. The specific epithet loong is a Latinized appositive noun derived from the Chinese word “龙” (lóng), meaning “loong” or “dragon.” In Chinese culture, snakes are often regarded as “little dragons” or “lesser dragons” because of their serpentine form and symbolic association with the dragon (loong). The name also refers to the type locality, Qinglongxia (青龙峡), which literally translates to “Green Dragon Gorge.” The vivid green coloration of the new species echoes this name, establishing both symbolic and geographical connections. In addition, the year 2025, which marks the discovery and collection of this species, corresponds to the Year of the Snake in the lunar calendar. We therefore propose the common names “昆明竹叶青蛇” (Kūn Míng Zhú Yè Qīng Shé) in Chinese and “Kunming Green Pit Viper” in English, referring to its type locality Kunming City, Yunnan Province, China.
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| Paratypes of Trimeresurus loong sp. nov. A. Dorsal view of the head; B. Lateral view of the head; C. Ventral view of the head; D. Lateral view of the body; E. Ventral view of the body. A1–E1. QHU R2025028, adult male; A2–E2. QHU R2025029, subadult male; A3–E3. QHU R2025030, subadult male; A4–E4. QHU R2025031, adult female; A5–E5. QHU R2025032, adult female. Photographs by Y.H. Xu. |
Yuhao Xu, Jundong Deng, Tierui Zhang, Tan Van Nguyen, Shiyang Weng, Nikolay A. Poyarkov, Gernot Vogel, Fanyue Sun, Chencan Liao and Lifang Peng. 2025. A ‘Little Dragon’ from Kunming City: A New Green Pit Viper from Yunnan Province, China (Squamata, Viperidae, Trimeresurus). Zoosystematics and Evolution. 101(4): 2267-2293. DOI: doi.org/10.3897/zse.101.175879
