The Mary River turtle is an endangered species of short-necked turtle in the family Chelidae. The species is endemic to the Mary River in south-east Queensland, Australia. Although this turtle was known to inhabit the Mary River for nearly 30 years, it was not until 1994 that it was recognised as a new species. There has been a dramatic decrease in its population due to low reproduction rates and an increase of depredation on nests.

Chelidae is one of three living families of the turtle suborder Pleurodira, and are commonly called Austro-South American side-neck turtles. The family is distributed in Australia, New Guinea, parts of Indonesia, and throughout most of South America. It is a large family of turtles with a significant fossil history dating back to the Cretaceous. The family is entirely Gondwanan in origin, with no members found outside Gondwana, either in the present day or as a fossil.