Varanus giganteus, Perentie mounted goanna specimen
Image: Heath Warwick
Source: Museum Victoria
Question: What is the largest lizard in Australia?
Answer: The largest lizard in Australia is the Perentie (Varanus giganteus). It can grow up to 2.5 metres in length and at maturity can weigh up to 15kg. General physical characteristics include a forked tongue, long slender neck, flattened head, strong tail, and five clawed toes at the end of very powerful legs. This lizard is usually a rich brown colour with large cream or yellow markings.
The Perentie lizard may be found living in arid regions from Western Queensland to coastal Western Australia, usually around rocky hills and outcrops. The female Perentie lizard will lay around six to twelve eggs in termite mounds where the activity of the insects provides constant warmth for the offspring.
Perenties are carnivores, and have been known to catch rabbits and smaller species of kangaroo. They also forage on turtle eggs, insects, birds, mammals, carrion and other reptiles (including juvenile Perenties). These lizards will track their prey by sight or by sensing with their tongue.
If threatened, they distend a large neck pouch and expel a rattling hiss as a defence mechanism. Should this dramatic display fail, the Perentie lunges forward and strikes its opponent before quickly turning and fleeing to hide in the nearest rocky crevice or burrow.
The Perentie belongs to the category of lizard known as a monitor, and as such it is related to the much larger Komodo Dragon. There are presently 25 different species of monitor found in Australia, just less than half of the world’s known species of monitors. The Perentie’s cousin, the Lace Monitor (Varanus varius), also known as the Tree Goanna, is the largest monitor lizard in Victoria.