The Asian water monitor (Varanus salvator), also called common water monitor, is a large varanid lizard native to South and Southeast Asia. It is one of the most common monitor lizards in Asia, ranging from Sri Lanka and coastal northeast India to Indochina, Malay Peninsula, and Indonesianislands where it lives close to water. It is listed as Least Concern on the IUCN Red List. It was described by Laurenti in 1768 and is among the largest squamates in the world.
The Asian water monitor is also called Malayan water monitor, common water monitor, two-banded monitor, rice lizard, ring lizard, plain lizardand no-mark lizard, as well as simply water monitor.
The water monitor is a large species of monitor lizard. Breeding maturity is attained for males when they are a relatively modest 40 cm (16 in) long and weigh 1 kg (2.2 lb), and for females at 50 cm (20 in). However, they grow much larger throughout life, with males being larger than females. Adults rarely exceed 1.5–2 m (4.9–6.6 ft) in length, but the largest specimen on record, from Sri Lanka, measured 3.21 m (10.5 ft). A common mature weight of V. salvator can be 19.5 kg (43 lb).
Water monitors defend themselves using their tails, claws, and jaws. They are excellent swimmers, using the raised fin on their tails to steer through water. They are carnivores, and consume a wide range of prey. They are known to eat fish, frogs, rodents, birds, crabs, and snakes.They have also been known to eat turtles, as well as young crocodiles and crocodile eggs.Water monitors have been observed eating catfish in a fashion similar to a mammalian carnivore, tearing off chunks of meat with their sharp teeth while holding it with their front legs and then separating different parts of the fish for sequential consumption.