Monday, November 2, 2020

[Herpetology • 2020] Trimeresurus davidi • A New Species of Green Pit Viper of the Genus Trimeresurus Lacépède, 1804 (Serpentes: Viperidae) from the Nicobar Archipelago, Indian Ocean


Trimeresurus davidi
Chandramouli, Campbell & Vogel, 2020


Abstract
A new species of green pit viper of the genus Trimeresurus, in the T. albolabris complex, is described from Car Nicobar Island of the Nicobar Archipelago, Indian Ocean. The new species, Trimeresurus davidi sp. nov., can be distinguished from all other members of this group by the following characteristics: medium to large body size (277–835 mm SVL); dorsal scales in a series of 21–25:21–23:15–17 rows; nasal partly fused with the frst supralabial; 166–179 ventrals, 58–70 subcaudals; one preocular; 2–3 postoculars; 10–12 supralabials; 12–15 infralabials; two internasals usually in contact with each other; 11–14 cephalic scales; verdant green dorsal and ventral color, absence of white ventrolateral stripes along the sides of the body; males with a white supralabial streak, bordered by a reddish tinge above; a pair of white and red stripes along the sides of the tail in both sexes; a reddish brown colored tail and a greenish iris. The new species is endemic to Car Nicobar Island of the Nicobar Archipelago, and should be regarded as an Endangered species owing to its restricted distribution range. 

Keywords. Endangered, endemic species, Nicobar Islands, Reptilia, Squamata, Trimeresurus albolabris complex 



Fig. 2. Trimeresurus davidi sp. nov. in life from Car Nicobar
(top and middle: males, bottom: female).

Trimeresurus davidi sp. nov.

Trimeresurus albolabris – Vijayakumar and David (2006). 
Trimeresurus albolabris – Smith (1943) part, Vogel (2008) part, Vogel et al. (2014) part.


Etymology. The specific epithet is a patronym, named in genitive singular case, honoring Patrick David, an eminent reptile taxonomist for his immense contribution to the systematics of Asian pit vipers and, in particular, to the Nicobar snake fauna.

 Diagnosis. Trimeresurus davidi sp. nov. is an arboreal member of the genus Trimeresurus restricted to the Car Nicobar Island of the Nicobar archipelago, characterized by: medium to large sized body (277–835 mm SVL); dorsal scales in a series of 21–25:21–23:15–17 rows; nasal partly fused with the first supralabial; 166–179 ventrals; 46–70 subcaudals; one preocular; 2–3 postoculars; 10–12 supralabials; 12–15 infralabials; two internasals usually in contact with each other; 11–14 cephalic scales; relative tail length (TaL/TL) ranging from 0.143–0.20; dorsal and ventral verdant green in color, lacking white ventrolateral stripes; males with a white supralabial streak, bordered by a reddish tinge above; a pair of white and red stripes along the sides of the tail in both males and females; a reddish brown colored tail and a greenish iris; hemipenis reaching the 13th caudal plate.  


Fig. 3. Distribution of members of the Trimeresurus albolabris complex showing the type locality and distribution of Trimeresurus davidi sp. nov.


S.R. Chandramouli, Patrick D. Campbell and Gernot Vogel. 2020. A New Species of Green Pit Viper of the Genus Trimeresurus Lacépède, 1804 (Reptilia: Serpentes: Viperidae) from the Nicobar Archipelago, Indian Ocean. Amphibian & Reptile Conservation. 14(3) [Taxonomy Section]: 169–176 (e264).