Acrochordus javanicus
Juvenile in Malaysia (© Gernot Vogel) 
captive (© Frank Teigler) 
captive (© acrochordus.com) 
captive (© acrochordus.com)
English name: Javan Wart Snake (aka: “Elephant Trunk Snake” or “Javan File Snake”)
Scientific name: Acrochordus javanicus
Thai name: งูงวงชาง (Ngu Nguang-chang)
Description: To 290cm long. Thick body and loose folds of skin lead to the common name “Elephant Trunk Snake”. Skin is covered with small pyramid-like scales that are rough to the touch, giving the alternative common name “file snake”. Head is flat and wide with the nostrils and eyes positioned on top. Tail is round. Body is olive-brown to grayish-black on top, fading to pale yellow with borken-up dark lines and blotches on the sides.
Similar Species: Little File Snake is smaller and has cream bands rather than dark lines/blotches.
Sea Snakes of the Elapidae family have different scale types and a paddle-shaped tail, though the differences may be subtle. Never handle any snake, especially not one you find in the ocean, unless you are absolutely certain of its identification.
Habitat: The Javan Wart Snake is occasionally found in the ocean, but prefers the brackish or fresh water of slow-moving rivers and streams in coastal areas. It is able to live in ditches and canals of agricultural land. It becomes almost entirely aquatic as it matures and has difficulty moving on land as an adult. Usually hides in the roots of trees lining the water during the day, coming out into open water at night to hunt.
Place in the ecosystem: The Javan Wart Snake feeds on fish and frogs. Smaller juveniles may be eaten by large fish, monitors and wading birds.
Danger to humans: Has no venom, rarely bites and is not dangerous, though it can deliver a painful bite if it chooses to do so.
Conservation status and threats: The Javan Wart Snake is currently common and populations appear able to withstand a great deal of hunting pressure and habitat degradation. Still, there are concerns as hundreds of thousands are killed each year for their skins, which are turned into leather after the scales are removed. Their flesh is also sold in markets and eaten.
Interesting facts: The Javan Wart Snake surprises fish by ambushing them at the bottom of the water bodies where it lives. When it grabs a fish it grips it with the coils of its body, which are able to hold onto the slippery fish due to the rough, triangular scales.
Female Javan Wart Snakes can be more than 50% longer and much thicker than the males, an unusual extreme in sexual dimorphism among snakes.
References:
IUCN Redlist: Acrochordus javanicus
A Photographic Guide to Snakes and Other Reptiles of Peninsular Malaysia, Singapore and Thailand
A Field Guide to the Reptiles of South-East Asia
Guide to the Snakes of South Vietnam
Snakes of Thailand and their Husbandry
Reptiles and Amphibians of Thailand 