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| Lycodon irwini Naveen, Mirza, Choure & Chandramouli, 2025 |
Abstract
The Nicobar Archipelago, a biodiversity hotspot in the Bay of Bengal, harbours several poorly studied and endemic reptile lineages. Several species of snakes from these islands are known to science with just one or a handful of specimens. One such taxon, historically identified as Lycodon subcinctus Boie, 1827, has remained taxonomically unresolved, known only from a single sighting on Great Nicobar Island to date. Recent taxonomic revisions of the L. subcinctus complex enabled us to reassess the status of the population from the Nicobar Islands. Studies suggested that the species is distinct, and a re-examination of museum material and newly collected specimens, combined with molecular analyses, confirms the distinctiveness of the species and is here described as a new species, Lycodon irwini sp. nov. Given its rarity and restriction to Great Nicobar Island, and taking into account potential threats we recommend that the new species be classified as ‘Endangered’ under the IUCN Red List criteria.
Key Words: Colubridae, conservation, island, phylogeny, Sundaland, systematics, taxonomy, wolf snakes
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| Lycodon irwini sp. nov., adult female holotype (Voucher no. DOSMB 05114), head views. a. Dorsal aspect; b. Ventral aspect; c. Right lateral aspect; d. Left lateral aspect. |
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| Lycodon irwini sp. nov., dorsolateral view of an adult female in life. |
Lycodon irwini sp. nov.
Diagnosis. A Lycodon characterized by the following characters: body size fairly large, maximum known total length up to 1197 mm, slender; preocular maybe present or absent (present here only in the holotype), loreal touching orbit; dorsal scale rows 17-17-15, anterior part of the body with smooth scales and posterior parts with the outermost rows smooth and the remaining rows feebly keeled; ventral scales 223–238; subcaudals 78–94, paired; TaL/TL 0.20–0.23; supralabials 8, with the 3rd–5th touching orbit; postoculars 2/2; cloacal plate divided. Dorsum overall in a shade of glossy black, lacking bands and ventrally greyish black with cream ventrolateral ridge.
Etymology. The specific epithet is a patronym honouring the late Stephen Robert Irwin (22 February 1962–1964 September 2006), the renowned Australian zookeeper, conservationist, television personality, and wildlife educator. His passion and dedication to wildlife education and conservation have inspired naturalists and conservationists worldwide, including the authors of this paper.
R. S. Naveen, Zeeshan A. Mirza, Girish Choure and S. R. Chandramouli. 2025. A ‘Crikey’ New Snake: An insular Lycodon Fitzinger, 1826 (Squamata, Colubridae) from the Nicobar Archipelago, India. Evolutionary Systematics. 9(2): 221-228. DOI: doi.org/10.3897/evolsyst.9.170645
