Testudinidae:

They have high domed shells and stout, heavily scaled limbs (Malacochersus is an exception with a dorsoventrally compressed shell). The head and limbs can be fully withdrawn into the shell. The genera Testudo and Pyxis have hinged plastrons while members of the genus Kinyxis have, uniquely among tortoises, a hinged carapace that allows it to be lowered over the hindquarters