A new endemic karst-associated species of lance-headed pit viper (Squamata, Viperidae, Protobothrops) from Laos

By

Grassby-Lewis, Rupert J.
Brakels, Peter
Maury, Nathanael
Sitthivong, Saly
Frohlich, David
Pawangkhanant, Parinya
Idiiatullina, Sabira S.
Nguyen, Tan
Poyarkov, Nikolay

Type

Article

Date of Publication

2025-2-25

Original Publication

Herpetozoa

Volume

38

Pages

43--60

Subjects

Indochina , Limestone , molecular phylogeny , Morphology , Protobothrops flavirostris sp. nov. , systematics , Vientiane Province

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/herpetozoa.38.e146004

 

Abstract

We describe a new species of lance-headed pit viper from north-western Laos, based on morphological and molecular (6092 bp from cyt b, ND4, COI, 12S rRNA and 16S rRNA mitochondrial DNA genes and c-mos and RAG1 nuclear DNA genes) lines of evidence. Protobothrops flavirostrissp. nov. is easily distinguished from its congeners by the following combination of morphological characters: dorsal scales in 23–21–17 rows, all keeled; ventral scales 215; subcaudal scales 79, all paired; supralabials 7–8; infralabials 10; horn-like projections on supraoculars absent; head triangular with a typical lance-shaped pattern on its dorsal surface; three faint dark vertical stripes on the snout; head blackish-brown with rostral, nasals, preoculars, loreals and the two anterior supralabials, as well as the anterior parts of supraoculars yellow-orange; dorsal surfaces of body and tail brown or greyish-brown, dorsum with large dark reddish-brown cross-shaped blotches, edged in black, somewhat fused together forming an interrupted zigzag line and a row of large brown ventrolateral blotches on each side. The new species differs from the morphologically similar species Protobothrops kelomohy by a significant divergence in cytochrome b mitochondrial DNA gene sequences (p = 7.8%). The new species is currently known only from tropical limestone forest of Vientiane Province, north-western Laos (elevation 362 m a.s.l.). We suggest the new species be considered as Endangered (EN) following the IUCN’s Red List categories.