Venomous and Dangerous!
English name: Mangrove Pit Viper (aka “Shore Pit Viper”)
Scientific name: Trimeresurus purpureomaculatus (formerly Cryptelytrops purpureomaculatus)
Thai name: Ngu Pang-ka
Description: To 104cm long. Average girth with a characteristic broad triangular head. Scales are heavily keeled, giving the body a rough appearance. Heat-sensing pits are located on the head between the nose and each eye. Body is brown, gray, olive, or greenish-yellow above and lighter below, with large dark blotches across the back and a white stripe on the sides.
Similar Species: Green pit vipers (Trimeresurus albolabris and Trimeresurus macrops) are always green without the dark blotching.
Eastern Russell’s Viper has smaller, more distinct blotches and is not found in mangrove forests.
Many-spotted Cat Snake is more slender with a smaller head and has smaller, more distinct blotches.
Habitat: Found in mangrove and other coastal forests. Occasionally found further inland along canals leading in from the ocean. Usually seen 1 to 2 meters off the ground or water in trees or bushes.
Place in the ecosystem: Eats frogs, lizards, and small mammals. May be eaten by birds of prey and wading birds.
Danger to humans: The Mangrove Pit Viper can be an aggressive species with a dangerous bite. Bites result in intense pain, swelling, necrosis of flesh, and in some cases severe systemic bleeding. Fatalities are rare but the hemorrhagic nature of the venom can lead to serious medical problems. Anyone who is bitten by a pit viper should be taken to the hospital as quickly as possible.
Conservation status and threats: No known conservation threats.
Interesting facts: Southeast Asian Pit Vipers are not as deadly as the local cobras, kraits, and true vipers, but still can do significant damage. Thailand’s pit vipers have a “hemorrhagic” venom that causes pain, swelling, coagulopathy, and some tissue damage. In serious cases severe coagulopathy, internal bleeding, and necrosis of the flesh can develop. Pit Viper-specific antivenom is available and should be administered as soon as possible to relieve symptoms and decrease long-term effects.
If you or someone you are with is bitten by a Mangrove Pit Viper, the most important steps are to:
1) Keep the victim calm, having them lie down with the bite mark below the heart if possible.
2) Take a picture of the snake to confirm identification for the hospital.
3) Get the victim to a hospital immediately where professional treatment can take place and antivenom can be given.
Wikipedia entry for Trimeresurus purpureomaculatus
Ecology Asia: Shore Pit Viper
Biological properties of Trimeresurus purpureomaculatus (shore pit viper) venom and its fractions.
A national hospital-based survey of snakes responsible for bites in Thailand
Queen Saovabha Memorial Institute: Snake Farm
Snake Bites and their Treatment
A Field Guide to the Reptiles of South-East Asia
Snakes of Thailand and their Husbandry