Varanosaurus is an extinct genus of early pelycosaur synapsid that lived during the early Permian

Permian

The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...

 (260 million years ago).

As its name implies, Varanosaurus looked very similar to present-day monitor lizard

Monitor lizard

Monitor lizards are usually large reptiles, although some can be as small as in length. They have long necks, powerful tails and claws, and well-developed limbs. Most species are terrestrial, but arboreal and semiaquatic monitors are also known...

s. It had a flattened, elongated skull and a pointed snout with a row of sharp teeth, including two pairs of conspicuous pseudocanines, implying that it was an active predator. It was a small, nimble reptile, up to 1.5 metres (4.9 ft) long.

Varanosaurus probably lived in swamp

Swamp

A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...

s, competing with the larger Ophiacodon

Ophiacodon

Ophiacodon was a large pelycosaur. Its fossils were found in Joggins, Nova Scotia, Canada.Ophiacodon was at least two meters in length, and the largest species were up to . It is estimated to have weighed from . The size of the various species increased during the Early Permian epoch until its...

for food.