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| Trimeresurus erythrochloris Pawangkhanant, Idiiatullina, Smits, Dugdale, Pierce, Suwannapoom & Poyarkov, 2025 |
Abstract
We describe a new species of karst-dwelling pitviper from Sa Kaeo Province in eastern Thailand based on morphological and molecular (2,296 bp from cyt b, ND4, and 16S rRNA mitochondrial DNA genes) lines of evidence. Our phylogenetic analysis places the new species as a sister lineage of Trimeresurus venustus (p = 2.7% and 3.7% for cyt b and ND4 genes, respectively). It is also closely related to T. cardamomensis (p = 2.1% and 2.6% for cyt b and ND4 genes, respectively). To date, the new species is known from only two adult specimens, and its distribution seems to be restricted to a narrow limestone karst area in the province of Sa Kaeo in Thailand near the national border with Cambodia. Additional studies are required to understand its life history, distribution, and conservation status. The discovery of this new species brings the total number of known Trimeresurus to 51 species, 19 of which occur in Thailand, including five that are endemic to this country.
Key words: limestone, morphology, molecular phylogeny, systematics, Sa Kaeo Province
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| Trimeresurus erythrochloris sp. nov. adult female |
Trimeresurus erythrochloris sp. nov.
Diagnosis. The new species differs from other members of the subgenus Trimeresurus by the following combination of characters: dorsal scales in 23-21-15 rows, moderately keeled except the outermost rows, which are smooth; ventral scales 164–172; subcaudals 54–67, all paired; iris golden yellow in both sexes; body dorsally grass green with irregular, serrated, reddish-brown transverse markings; suborbital stripe white and wide in male, absent in female; ventrolateral stripe distinct, present on the first few dorsal scale rows, white and red in male, white in female; throat, chin, and lower labials light turquoise; ventral surfaces pale blue in male, pale green in female; tail dorsally light brick-red mottled with dark spots, ventrally with irregular white markings; hemipenis with welldeveloped pointed almost spine-like papillae at its base.
Etymology. The species name “erythrochloris” is a Latinized adjective in the nominative singular, masculine gender, derived from the classical Greek adjective eruthros (ἐρυθρός), “erythros”, meaning “red”, and from the adjective chloros (χλωρός), “chloris”, meaning “green”. The species name is given in reference to the beautiful dorsal coloration of the new species, which consists of red bands on the green background.
We suggest the following common names for the new species:
“Ngu Khiew Hang Mai Lai Yhak” (งูเขียวหางไหม้ลายหยัก) (in Thai),
“Red-barred Green Pitviper” (in English), and
“Krasno-zelenaya bambukovaya kufiya” (Красно-зеленая бамбуковая куфия) (in Russian).
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| Habitat of Trimeresurus erythrochloris sp. nov. (in life) at the type locality in ..., Sa Kaeo, Thailand. Photo: T. Smits. |
Parinya Pawangkhanant, Sabira S. Idiiatullina, Ton Smits, Ian Dugdale, Andrew Pierce, Chatmongkon Suwannapoom and Nikolay A. Poyarkov. 2025. A New Species of Karst-associated Pitviper of the Trimeresurus kanburiensis Complex (Squamata: Viperidae) from eastern Thailand. TAPROBANICA. 14(1); 1–15. DOI: doi.org/10.47605/tapro.v14i1.347
