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| Trimeresurus ciliaris sp. nov. Idiiatullina, Pawangkhanant, Tawan, Worranuch, Dechochai, Suwannapoom, Nguyen, Chanhome & Poyarkov, 2023 |
Abstract
We describe a new species of pitvipers from Trang Province of Thailand, near the Thailand–Malaysian border, based on morphological and molecular (2427 bp from cyt b, ND4, and 16S rRNA mitochondrial DNA genes) lines of evidence. Morphologically, Trimeresurus ciliaris sp. nov. is distinguished from its congeners by the following combination of morphological characters: a long papillose hemipenis; first supralabial and nasal scale fused; three to four small supraocular scales; internasals not in contact; small scale between nasal and the scale formed by the fused second supralabial and loreal present; dorsal scales in 17–17–15 rows across the body; ventral scales 172–175 in males, 171 in female; subcaudal scales 59–63 in males, 61 in female, all paired; in life an emerald-green dorsum with reddish-brown bands; creamy-white venter lacking dark dots or stripes on the lateral sides of the ventrals; white vertebral spots present in both sexes on every two or three dorsal scales; dark brown spots forming discontinuous pattern present on 1–3 lateral dorsal scale rows; males with reddish-brown postocular stripe. The new species forms a distinct clade on the phylogenetic tree of the genus Trimeresurus and differs from the morphologically similar species T. venustus by a significant divergence in cytochrome b mitochondrial DNA gene sequences (p = 12.5%). The new species is currently known from a small karstic area in the Nakawan Range spanning the border of Thailand and Malaysia, in particular in limestone forests in Trang and Satun provinces (Thailand); it likely also occurs in the adjacent parts of Perlis State (Malaysia). Our study also suggests that the taxonomy of T. kanburiensis species complex requires further studies; in particular our study suggests that the status of populations from Chumphon Province of Thailand and Pulau Langkawi Island of Malaysia should be re-assessed.
Keywords: Biodiversity, Malaysia, morphology, phylogenetics, Reptilia, taxonomy, Thai-Malay Peninsula, Trimeresurus ciliaris sp. nov., Trimeresurus kanburiensis species complex
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| The holotype of Trimeresurus ciliaris sp. nov. in life (ZMMU Re-17661, adult male) from Thum Khao Ting, Palian District, Trang Province, Thailand. A dorsolateral and B ventral view of body; C head in dorsal, D in ventral, E in lateral right, and F in lateral left aspects; G right hemipenis, partially everted; H close-up of dorsal scales. Photographs by P. Pawangkhanant. |
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| Habitat of Trimeresurus ciliaris sp. nov. A microhabitat of the new species near the Thum Khao Ting Cave, Palian District, Trang Province, Thailand; B holotype ZMMU Re-17661, adult male, in life in situ; C paratype QSMI 1538, adult female, in life in situ; D–E male specimen from Wang Kelian, Perlis State, Malaysia (not collected). Photographs by P. Pawangkhanant (A–C) and Azrul Azrizal Azmy (D–E). |
Trimeresurus ciliaris sp. nov.
Chresonymy: Cryptelytrops cf. venustus (partim): Chan et al. (2011: 258).
Diagnosis: A species of the genus Trimeresurus which is assigned to the subgenus Trimeresurus based on the following morphological attributes: a long papillose or calyculate hemipenis and partially fused first supralabial and nasal scales (Malhotra and Thorpe 2004a; David et al. 2011). The new species Trimeresurus ciliaris sp. nov. can be distinguished from all other congeneric species by the following combination of morphological characters: three or four small convex supraocular scales; internasals not in contact; small scale between nasal and the scale formed by the fused second supralabial and loreal present; dorsal scales in 17–17–15 rows; ventral scales 172–175 in males, 171 in a single female; subcaudal scales 59–63 in males, 52 in a single female, all paired; in life an emerald-green dorsum with reddish-brown cross-bands; creamy-white venter lacking dark dots or stripes on the lateral sides of the ventrals; iris olive-green with faded-brown horizontal stripe; tail dark brown mottled with rusty spots; white vertebral spots present in both sexes located approximately every two or three dorsal scales; dark brown spots forming discontinuous pattern present on 1–3 lateral dorsal scale rows; males having a reddish-brown postocular stripe.
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| Comparison of body coloration between males of A Trimeresurus ciliaris sp. nov.; B T. kanburiensis; C T. kuiburi; and D T. venustus s. str. Photographs by P. Pawangkhanant (A, B, D) and T. Woranuch (C). |
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| Comparison of head coloration (left profile and dorsal view of the head) between males of A–B Trimeresurus ciliaris sp. nov.; C–D T. kanburiensis; E–F T. kuiburi; and G–H T. venustus s. str. Photographs by P. Pawangkhanant (A–D), A. Kaosung (E–F, H) and M. Naiduangchan (G). |
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| Variation in head scalation and coloration in male paratypes of Trimeresurus ciliaris sp. nov.: A ZMMU Re-17661; B ZMMU Re-17662; C AUP-02011; and D ZMMU Re-17663. See Table 4 for details. Photographs by P. Pawangkhanant. |
Etymology: The species name “ciliaris” is a Latin adjective in the nominative singular, masculine gender, derived from Latin word “cilium” meaning “an eyelash”, and is given in reference to the characteristic small and distinct supraocular scales in the new species, which resemble eyelashes or eyebrows in lateral view.
We suggest the following common names for the new species: “Ngu Hang Mhai Khao Hin Poon” (งูหางไหม้เขาหินปูน) (in Thai), “Limestone Eyelash Pitviper” (in English), and “Resnitchataya ukrashennaya kufiya” (in Russian).
Sabira S. Idiiatullina, Parinya Pawangkhanant, Tanapong Tawan, Thanawut Worranuch, Bunyarit Dechochai, Chatmongkon Suwannapoom, Tan Van Nguyen, Lawan Chanhome and Nikolay A. Poyarkov. 2023. Limestone Jewel: A New colourful Karst-dwelling Pitviper (Serpentes: Viperidae: Trimeresurus) from the poorly explored borderlands of southern peninsular Thailand. Vertebrate Zoology. 73: 697-716. DOI: 10.3897/vz.73.e109854
