family of terrestrial turtles, or tortoises (order Chelonia). The group is closely related to turtles in the family Emydidae. The approximately 40 species are characterized by heavy domed shells, elephantine limbs, and slow-moving, herbivorous habits. The family is widespread in South America and Africa, and representatives occur in warm regions of North America, Europe, and Asia. The best known members of the family are the giant tortoises of the Galápagos Islands and the gopher tortoises of the American south and west.