SPOTTED TREE MONITOR Varanus timorensis Gray, 1831
This 70-cm lizard is found throughout tropical parts of Northern Australia. Its colour is highly variable, with younger specimens often being much more brilliantly coloured than the adults.
The Spotted Tree Monitor lives in various habitats but is most common in savannah woodland habitat. This tree-dweller is usually seen moving around tree trunks and branches where it feeds on insects, geckoes, etc. If found foraging on the ground it will run up the nearest tree. When resting, the Spotted Tree Monitor is found in hollow logs and hollow tree branches, or under loose bark.

The above was from the book Australian Reptiles and Frogs by Raymond Hoser and now available on a fantastic CD-Rom along with a vast amount of other information, papers and the like on reptiles, frogs and other wildlife.