A new genus and species of extinct lizard is described from the Early Pliocene to Early Pleistocene deposits of Wellington Caves, New South Wales, Australia. The description is based on the anterior half of a left mandibular ramus that shows a suite of unusual characteristics. The fossil is referred to the Scincidae, based on its combination of a distinct coronoid process of the dentary and completely fused Meckelian groove, but it differs significantly from living scincids in several respects. The dental sulcus disappears posterior to the symphysis. The dentition shows slight enlargement of the teeth posteriorly, with the terminal tooth the largest. The new taxon has an exceptionally massive jaw, with a hypertrophied symphysis and coronoid region and the angle at the symphysis suggests a short, deep snout. The new species is not obviously related to any of the major extant scincid lineages.