Genus Macroclemys

Gray, 1856
Alligator snapping turtles

The single living species within this genus, Macroclemys temminckii, the alligator snapping turtle, is one of the unique turtles of the world. It is probably the heaviest hard-shelled freshwater turtle, growing to 80 cm and weighing as much as 113 kg, and is almost completely aquatic: females leave the water only to oviposit, and adult males apparently occasionally emerge only to bask.