Lycodon Tiwarii

Lycodon tiwarii, commonly known as the Andaman wolf snake or Tiwari’s wolf snake, is a nonvenomous colubrid snake endemic to the Andaman and Nicobar Islands of India. It is a relatively little-known insular species that forms part of the distinctive herpetofauna of these tropical island groups. Owing to its restricted distribution and limited field observations, Lycodon tiwarii is primarily of scientific importance in studies of island biogeography, endemism, and conservation of reptiles in the eastern Indian Ocean region.
Lycodon tiwarii belongs to the genus Lycodon, a group commonly referred to as wolf snakes. Members of this genus are characterised by nocturnal habits, terrestrial or semi-terrestrial lifestyles, and enlarged anterior teeth adapted for grasping prey rather than envenomation. Like other wolf snakes, L. tiwarii is harmless to humans.

Taxonomy and Systematic Position

Lycodon tiwarii is a member of the family Colubridae, the largest family of snakes, encompassing a wide range of mostly nonvenomous species. The genus Lycodon is distributed across South, Southeast, and East Asia and includes numerous species adapted to diverse habitats, from mainland forests to isolated islands.
The species was described relatively recently in comparison to many mainland Indian snakes, reflecting the historically limited herpetological exploration of the Andaman and Nicobar archipelago. Taxonomic clarification of island wolf snakes has been aided by detailed morphological studies and the examination of newly collected material from these islands.
Within the genus, Lycodon tiwarii is recognised as a distinct species based on morphological features and its geographically isolated range. It is not known to have any recognised subspecies.

Geographic Distribution and Endemism

Lycodon tiwarii is endemic to the Andaman and Nicobar Islands, an Indian union territory located in the Bay of Bengal. Its distribution includes both the Andaman Islands and the Nicobar Islands, although records indicate that it may be unevenly distributed across individual islands within the archipelago.
The Andaman and Nicobar Islands are well known for high levels of endemism among amphibians and reptiles, owing to their long isolation from the Indian mainland and their complex geological history. Lycodon tiwarii is considered part of this endemic assemblage, contributing to the unique reptilian biodiversity of the region.
The species has been recorded in forested habitats and is presumed to occur primarily in relatively undisturbed environments, although detailed distributional surveys remain limited. Its insular nature makes it particularly vulnerable to habitat modification and ecological disturbances.

Habitat and Ecology

Specific ecological data on Lycodon tiwarii are scarce, but its general habitat preferences are inferred from related species and field observations from the Andaman and Nicobar Islands. It is believed to inhabit tropical evergreen and semi-evergreen forests, as well as forest edges and leaf-litter-rich ground layers.
Like other wolf snakes, Lycodon tiwarii is likely to be nocturnal and primarily terrestrial. During daylight hours, individuals probably seek shelter under logs, stones, bark, or within crevices. Nocturnal activity allows the species to avoid daytime heat and potential predators while coinciding with the activity periods of its prey.
Ecologically, Lycodon tiwarii is presumed to feed mainly on small reptiles, such as geckos and skinks, which are abundant in island forest ecosystems. Its role as a small predator contributes to regulating reptile populations within its habitat.

Morphology and General Characteristics

Detailed published descriptions of the external morphology of Lycodon tiwarii are limited, but it is generally consistent with the overall body plan of the genus Lycodon. The species is moderately slender, with a slightly flattened head that is only weakly distinct from the neck.
Wolf snakes typically exhibit smooth dorsal scales and contrasting colour patterns involving dark backgrounds with lighter bands or spots. Such patterns can serve as camouflage in leaf litter and forest floor environments. The eyes are usually moderate in size with round pupils, reflecting nocturnal activity.
As a nonvenomous colubrid, Lycodon tiwarii lacks venom glands and specialised fangs. Its enlarged anterior teeth are used for grasping and holding prey rather than injecting venom.

Behaviour and Defensive Strategies

Lycodon tiwarii is considered a secretive and non-aggressive snake. Like other members of the genus, it is unlikely to display overt aggression when encountered by humans. When disturbed, it may attempt to flee, remain motionless, or adopt mild defensive postures.
If handled, the snake may bite defensively, but such bites are harmless and of no medical significance. The resemblance of wolf snakes to some venomous species can occasionally lead to misidentification, although Lycodon tiwarii is less likely to be confused with kraits than some mainland congeners due to its insular distribution.
Its nocturnal habits and cryptic behaviour mean that encounters with humans are relatively uncommon.

Reproduction and Life History

Lycodon tiwarii is oviparous, reproducing by laying eggs. Beyond its oviparity, little detailed information is available regarding clutch size, breeding season, or incubation period for this species. However, based on related wolf snakes, reproduction likely coincides with periods of higher humidity and temperature, which are favourable for egg development.
Eggs are probably laid in concealed locations such as under leaf litter, inside rotting logs, or within soil cavities. Hatchlings are expected to be fully independent upon emergence and to resemble adults in general body form and coloration.
Further field studies are required to document the reproductive biology and life history traits of Lycodon tiwarii in detail.

Etymology

The specific name tiwarii is a patronym honouring the Indian zoologist Krishna Kant Tiwari, in recognition of his contributions to zoology and herpetology. The use of the Latin genitive suffix “-ii” follows standard zoological nomenclature for species named after individuals.
The etymology has been documented in authoritative works on reptile nomenclature, including The Eponym Dictionary of Reptiles, which provides historical context for species names derived from personal names.

Conservation and Scientific Significance

Although Lycodon tiwarii has not been as extensively studied as many mainland Indian snakes, its restricted island distribution makes it inherently vulnerable to environmental change. Habitat loss, deforestation, infrastructure development, and the introduction of invasive species pose potential threats to reptile populations across the Andaman and Nicobar Islands.
The species is of particular interest in biogeographical studies, as it contributes to understanding patterns of colonisation, speciation, and endemism in island systems. Research on Lycodon tiwarii has featured in broader works examining the amphibians and reptiles of the Andaman and Nicobar Islands, highlighting its role within the region’s unique herpetofauna.