True Vipers Of India: The Three Viperine Snakes Of The Country

A Russell's viper. Image credit: Davidvraju, CC BY-SA 4.0 via Wikimedia Commons

India’s vipers are often discussed as a single group, but the country’s viper fauna has two distinct evolutionary lineages. The larger and more diverse group is the pit vipers, or Crotalinae, which include bamboo, Malabar, and Himalayan pit vipers. The other is the Viperinae, or true vipers. In India, the latter is represented by three species: the Russell’s viper, the Indian saw-scaled viper, and the Levantine viper. The current Checklist of Snakes of India places all three in the subfamily Viperinae.

What Is A True Viper?

The term “true viper” refers to members of the subfamily Viperinae, within the family Viperidae. They are distinct from India’s pit vipers, which belong to Crotalinae. Both groups possess the characteristic long, hinged venom fangs associated with vipers, but pit vipers have an additional sensory structure: the loreal pit, a heat-sensitive organ between the eye and nostril. True vipers do not have these facial heat-sensing pits.

Russell’s Viper

Scientific name: Daboia russelii

A Russell's viper. Image credit: Prabhmeet Singh, CC BY-SA 4.0 via Wikimedia Commons.

Among India’s vipers, the Russell’s viper is one of the most familiar. It is a medically important species that is among the “Big Four” of India, responsible for the highest number of snakebite-related deaths in the country.

It has a heavy body, and the dorsal pattern usually consists of three rows of large, dark-edged oval or rounded markings. The pattern can be striking when the snake is exposed, but it also provides effective camouflage among dry vegetation, soil, and leaf litter.

The Russell’s viper occurs across large parts of the Indian subcontinent and is associated with a variety of habitats, including human-modified ones.

Saw-scaled Viper

Scientific name: Echis carinatus

A saw-scaled viper. Image credit: Dr. Raju Kasambe, CC BY-SA 4.0 via Wikimedia Commons.

This species is considerably smaller than the Russell’s viper, but its reputation in India is not based on size. It is adapted to relatively dry environments and can occur in deserts, semi-arid landscapes, rocky areas, scrub, and other open habitats. The rough, strongly keeled scales are one of its recognizable features. When threatened, the snake may rub sections of its body together, producing the characteristic rasping or “sawing” sound from which its common name is derived. It feeds on small vertebrates and other prey and is part of the food web of India’s drier ecosystems.

It is also among the “Big Four” species of India because of its historical importance in snakebite epidemiology.

Levantine Viper

Scientific name: Macrovipera lebetina

A Levantine viper. Image credit: Rashid Baradaran, CC BY-SA 4.0 via Wikimedia Commons.

This species is the least widespread of India’s three true vipers. The current ZSI checklist records the Levantine viper from the western Himalayas.

The species is considerably less frequently encountered than the other two on the list in India. Historical records and published accounts place it in the mountainous and rocky landscapes of Jammu and Kashmir. Its broader range extends from the eastern Mediterranean and the Middle East through Central and South Asia.

Its broader range extends from the eastern Mediterranean and the Middle East through Central and South Asia. The Indian population therefore, represents the eastern portion of a much larger distribution.