The Turtles

Turtles or chelonians are reptiles that appeared in the Late Triassic, 220 million years ago. Unmistakable by its peculiar protective armor, the shell, the oldest known fossil had armor only on its belly, as can be seen in this reconstruction of its appearance in life.

At present, there are only 325 species in the world (less than 4% of the total living reptiles). Half of these are threatened by habitat transformation, nests depredation, commercial exploitation as food, medicine, or for recreational purposes, alteration of nesting sites, and accidental death in fishing nets. They are the most endangered vertebrates on the planet, more than amphibians, fish, birds, and mammals.

The leatherback turtle, Dermochelys coriacea (photo on the right), reaching two meters long and weighing up to 900 kilograms, is the largest living reptile.

The species of the center of Argentina (bottom row photos) are the lagoon turtle (Phrynops hilarii), the snake-necked turtle (Hydromedusa tectifera) and the very popular common tortoise (Chelonoidis chilensis).