Varanus scalaris is a member of the subgenera Odatria. With a total length of 65 cm it is part of the smaller monitor species. Within the last years the nomenclature of this monitor species has changed repeatedly, MERTENS (1941, 1942b, 1942d) described it still as subspecies of V. timorensis, simultaneously he described V. timorensis similis as another subspecies (MERTENS 1958). STORR (1980) summarized both subspecieses for Western Australia under V. timorensis scalaris. 1983 this subspecies is raised to species status by STORR et al. (1983b). WILSON & KNOWLES (1988) also take on the species name scalaris for the complete population on the Australian continent.
We would like to follow STORR (1980) and STORR et al. (1983b) in this place and for the Australian form of the Timor Monitor use Varanus scalaris as species name. The type specimen of V. t. similis, MERTENS has described in 1958, falls consequently into the variation of V. scalaris and has to be included into the synonymic list for this species therefore. All speciemen of V. t. similis which are known from New Guinea must consequently be taken into the synonymic list of V. timorensis.
Great variations in the phenotype are recognizable; the coloration of animals from northern parts of the Northern Territory and from the Kimberleys in Western Australia is mainly grey with small bright ocelli. The ocelli occasionally have a dark central spot, are ordered in several cross bands or form a reticulation. These animals are popularly described as the "dry forest form". Unlike this form the "rain forest form" from the rain forests of Cape York Peninsula in northern Queensland have very large bright ocelli, which are clearly distinguished from the dark grey background, forming 6-9 cross bands on the back. Alternating to these rows single bright scales form a thin band between those. Animals of the islands of the Sir Edward Pellew group have slightly different coloration and pattern. However, the name V. pellewensis indroduced for these monitors cannot be used until officially taxonomic studies are done.
All animals of this complex show a black temporal stripe which is surrounded by a bright band below. The head scales are small and smooth. Animals from the western distribution area often have a shiningly yellow orange throat. The nostril is situated at the side and is insignificantly closer to the tip of the snout than to the eye. 95 - 135 scale rows are around midbody. The tail is more or less round in diameter and the length is approximately 1.5 times as long as SVL. In the first half it shows a banded pattern, the coloration of the second half is uniformely medium warm grey. Animals of the Atherton Tableland in Queensland show a distinctive band pattern at the tail.

	Varanus scalaris Atherton Tableland, Qld	Varanus scalaris Almeden, Qld
Varanus scalaris Lake Argyle, WA			Varanus scalaris Darwin, NT

The distribution of Varanus scalaris extends from Cape York Peninsula in the east along the tropical north of Australia to Broome in the west.
V. scalaris is a tree climer and occurs in the rain forest of Cape York Peninsula in northern Queensland as well as in the dry Sklerophyll woods in Arnhemland.
To search for food, V. scalaris climbs down the trees to the ground to looks for food in from of insects, spiders and possible small skinks between the leaves. The monitors sleep under the loose bark of the trees (SCHMIDA 1971). Occasionally they also search for food at night there. VALENTIC (1996) observed, that V. scalaris could be found in tree hollows, which were simultaneously occupied as shelter by other residents (geckos, treefrogs). Smaller geckos were overpowered, as well as spiders, cockroaches, and other insects (MERTENS 1942d, 1958, KEAST 1959, WORRELL 1966, BUSTARD 1970, SWANSON 1976, STORR 1980, STORR et al. 1983b, HOSER 1989, COGGER 1992, EHMANN 1992).