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| Trimeresurus kraensis Idiiatullina, Pawangkhanant, Suwannapoom, Tawan, Chanhome, Nguyen, David, Vogel & Poyarkov, 2024 |
ABSTRACT
We describe a new species of karst-dwelling pitviper from Chumphon Province of Peninsular Thailand, in the Isthmus of Kra, based on morphological and molecular data (2427 bp from cyt b, ND4 and 16S rRNA mitochondrial DNA genes). Morphologically, Trimeresurus kraensis sp. nov. is distinguished from other congeners by the following combination of morphological characters: a dark/bottle-green dorsum with reddish-brown or purple crossbands; pale green venter lacking dark dots; stripes present on the lateral sides of the ventrals; internasals generally in contact; one large supraocular scale on each side of the head; iris pale copper; tail brown with dark purplish-brown crossbars; dorsal scales in 21–21–15 rows; ventral scales 167 in a single male, 169–171 in females; subcaudal scales 62 in a single male, 52–54 in females, all paired. White vertebral spots present in males, located on approximately every two or four dorsal scales; dark brown spots forming discontinuous pattern present on 1–3 lateral dorsal scale rows; males with reddish-brown postocular stripe with jagged edges. The new species differs from the morphologically similar species Trimeresurus venustus s. str. by a notable divergence in cytochrome b mitochondrial DNA gene sequences (p = 5.9%).
Keywords: Crotalinae, Trimeresurus kanburiensis complex, Peninsular Thailand, karst, taxonomy
Class Reptilia Laurenti, 1768
Order Squamata Oppel, 1811
Suborder Serpentes Linnaeus, 1758
Family Viperidae Oppel, 1811
Subfamily Crotalinae Oppel, 1811
Genus Trimeresurus Lacépède, 1804
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| Comparison of body colouration between members of the Trimeresurus kanburiensis species complex (males). A. Trimeresurus ciliaris Idiiatullina et al., 2023 from Trang Province, Thailand. B. T. kanburiensis Smith, 1943 from Kanchanaburi Province, Thailand. C. Trimeresurus kraensis sp. nov. from Chumphon Province, Thailand. D. T. cf. venustus Vogel, 1991 from Langkawi Island, Kedah State, Malaysia. E. T. kuiburi Sumontha et al., 2021 from Prachuap Khiri Khan Province, Thailand. F. T. venustus from Krabi Province, Thailand. Photographs by P. Pawangkhanant (A–C, F), T. Chalton (D), and T. Woranuch (E). |
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| Comparison of head colouration (left profile and dorsal view of the head) between members of the Trimeresurus kanburiensis species complex (males). A–B. Trimeresurus kraensis sp. nov. C–D. T. ciliaris Idiiatullina et al., 2023. E–F. T. kanburiensis Smith, 1943. G–H. T. kuiburi Sumontha et al., 2021. I–J. T. venustus Vogel, 1991. Photographs by P. Pawangkhanant (A–F), A. Kaosung (G–H, J) and M. Naiduangchan (I). |
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| The holotype of Trimeresurus kraensis sp. nov. in life (AUP-02036, adult female) from Wat Tham Sanook, Chumphon Province, Thailand. A. Dorsolateral view. B. Ventrolateral view. C. Close-up of dorsal scales. D. Left side of the head. E. Dorsal view of the head. F. Ventral view of the head. Photographs by P. Pawangkhanant. |
Trimeresurus kraensis sp. nov.
Diagnosis: The new species is assigned to the subgenus Trimeresurus based on the following morphological attributes: a long papillose hemipenis and partially fused first supralabial and nasal scales (Malhotra & Thorpe 2004a; Idiiatullina et al. 2023). The new species Trimeresurus kraensis sp. nov. is distinguished from all other species of the subgenus Trimeresurus by the following combination of morphological characters: (1) a dark olive-green or bottle green dorsum; (2) dorsal pattern consisting of about 60 reddish-brown or purple blotches, transversally elongate but not reaching the lower part of the flanks, two or three series of dark brown spots forming a discontinuous pattern on the 1st to 3rd dorsal scale rows and white vertebral spots present in males, located approximately on every two or four dorsal scales; (3) venter creamish-green with some dark brown spots; (4) tips of the ventral plates both cream and dark brown, forming a discontinuous, alternating pale and dark, ventrolateral stripe; (5) males with a reddish-brown postocular stripe; (6) internasals generally in contact behind the posteror tip of the rostral; (7) single large supraocular scale; (8) iris pale copper, (9) tail brown with dark purplish-brown crossbars; (10) dorsal scales in 21–21–15 rows; (11) ventral scales 167 in a single male, 169–171 in females; (12) subcaudal scales 62 in a single male, 52–54 in females, all paired.
Etymology: The species name is the modern Latin adjective ʻkraensisʼ in the nominative singular, masculine gender, combining the noun ʻKraʼ, from the name of the Kra Isthmus in Peninsular Thailand where the type locality of the species is located, and the Latin suffix ʻ-ensisʼ (-is, -e),meaning ʻfromʼ. The species name therefore means, ʻfrom Kraʼ. We suggest the following common names for the new species: งูหางแฮ่มชุมพร (Ngu Hang Ham Chumphorn) (in Thai), and Kra Isthmus Pitviper (English).
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| Habitat of Trimeresurus kraensis sp. nov. A. Macrohabitat of the new species near the Wat Tham Sanook, Chumphon Province, Thailand. B. Photos in life in situ, adult male (uncollected). C. Subadult female (paratype, ZMMU Re-17665). Photographs by P. Pawangkhanant (A), Rupert Grassby-Lewis (B), and N.A. Poyarkov (C). |
Sabira S. Idiiatullina; Parinya Pawangkhanant, Chatmongkon Suwannapoom, Tanapong Tawan, Lawan Chanhome, Tan Van Nguyen, Patrick David, Gernot Vogel and Nikolay A. Poyarkov. 2024. Another New Species of Karst-associated Pitviper (Serpentes, Viperidae: Trimeresurus) from the Isthmus of Kra, Peninsular Thailand. European Journal of Taxonomy. 930(1), 20–52. DOI: 10.5852/ejt.2024.930.2489
