tortoise, (family Testudinidae), any member of the turtle family Testudinidae. Formerly, the term tortoise was used to refer to any terrestrial turtle. The testudinids are easily recognized because all share a unique hind-limb anatomy made up of elephantine (or cylindrical) hind limbs and hind feet; each digit in their forefeet and hind feet contains two or fewer phalanges. With the exception of the pancake tortoise (Malacochersus tornieri), the shell is high domed. Shells of some species are nearly spherical with a flattened base. Tortoises are exclusively terrestrial and occur on all continents except Australia and Antarctica. They also inhabit many