Ask an expert
Stephen Mahony, Herpetological Technical Officer, Australian Museum
Q What’s the difference between a turtle and a tortoise? Bill Forrest, Tamworth, NSW
A Turtles and tortoises are reptiles that scientifically all belong to the order Testudines, which is presently divided into 15 families and ultimately more than 330 species. This is based on diversities between their appearance, behaviour, ecology and evolution.
The common terms we use only split them into three groups: turtles, tortoises and terrapins. But these names are simply general conventions and how they are used is not consistent. For example, in many parts of the world, aquatic species are termed turtles, while terrestrial species are termed tortoises, and terrapins fall somewhere between. However, in Australia, where no Testudines are fully terrestrial, a different convention has arisen: species with flippers are termed turtles while species with clawed feet are termed tortoises.