Abstract
We revisit the systematics of Sri Lankan wolf snakes, historically assigned to Lycodon aulicus and describe a new species using an integrative assessment of external morphology (morphometry, meristics, and hemipenial morphology), osteology (microCT), mitochondrial DNA (cytochrome b), and distributional data. Phylogenetic analyses of the mitochondrial cytochrome b gene recovered the L. aulicus group as a strongly supported monophyletic clade that includes five distinct lineages: (i) a Sri Lankan lineage currently referred to as L. aulicus, (ii) L. flavicollis from India, (iii) L. capucinus from the Sundaland region, (iv) L. zawi from Myanmar, and (v) the Sri Lankan endemic described herein as a new species. In our analyses, the new species is placed close to the Sri Lankan lineage currently identified as L. aulicus and to L. flavicollis, although support for some internal relationships is limited. Because the molecular representation of L. aulicus remains geographically restricted (including only a single sequenced Sri Lankan individual and no sequence data from the neotype locality in southwestern India), broader conclusions about the species boundaries, monophyly, and range-wide structure of L. aulicus should be treated as provisional working hypotheses. We do not attempt a range wide revision of L. aulicus sensu lato; we restrict our taxonomic actions and interpretations to (i) stabilizing name usage via type fixation and (ii) diagnosing the description of an overlooked Sri Lankan tri banded lineage.
Lycodon trifasciatus Amarasinghe, Aththanagoda, Ranasinghe, Vogel & Karunarathna, sp. nov.
Diagnosis. Lycodon trifasciatus sp. nov. is distinguished from other congeners by having the following combination of characters (Table 2): adults reach maximum SVL 615 mm; a single preocular; two postoculars; a single loreal scale; divided cloacal plate; nasal scale completely divided by the nostril; preocular in contact with frontal; ventrals 182–184 in 2 males and 192– 195 in 3 females; subcaudals 51–60+ in males and 40–65 in females; 2+3 temporals shorten; nine supralabials with 3rd–5 th in contact with eye; dorsal scale rows 17-17-15; tail length 16.2– 18.1% of total length in males; reddish or dark olive brown dorsum (rarely black) with three (rarely four) white striated crossbands only on the anterior part of the body; crossbands with thickness of 2–4 vertebral scales and 22–28 scales in-between crossbands; 28–33 vertebrate scales between the parietal and first crossband on the body; poorly visible collar mark on the nape; absence of white lip band.
A.A. Thasun Amarasinghe, Patrick D. Campbell, Sampath S. Seneviratne, Sanjaya Weerakkody, Joshua Mata, Stevie R. Kennedy-Gold, Anusha Aththanagoda, Bhanuka Ranasinghe, Gernot Vogel and Suranjan Karunarathna. 2026. Neotype Designation for Lycodon aulicus (Linnaeus, 1758) (Squamata: Colubridae) and Description of A New Species from Sri Lanka. TAPROBANICA. 15(2); DOI: doi.org/10.47605/tapro.v15i2.422




































