As suggested by these common names, a prominent characteristic of the genus is a large blue tongue that can be bared as bluff-warning to potential enemies.

All species are found on mainland Australia with the exception of Tiliqua gigas, which occurs in New Guinea and various islands of Indonesia.

The Tanimbar blue-tongued skink, a subspecies of Tiliqua scincoides, is also found on several small Indonesian islands between Australia and New Guinea.

Most species are diurnal, ground-foraging omnivores, feeding on a wide variety of insects, gastropods, flowers, fruits, and berries.

T. frangens, the largest known species of the genus, lived during the Pliocene and Pleistocene epoch around the Wellington Caves of New South Wales in Australia.