Softshell turtles are mostly carnivorous and commonly consume insects, molluscs, fish, crustaceans and amphibians, although a few species also eat plants or algae. They catch their food without the benefit of the sharp beak most turtles use, as they have fleshy lips covering their toothless jaws. Softshell turtles are, in turn, preyed upon by a wide variety of animals, particularly as eggs or juveniles.
Softshell turtles are named for their leathery shells, which lack the normal keratin scutes that harden the shells of other groups of turtles. Their bone structure in support of the shells is also much reduced, and their ribs, normally bonded to the shell throughout their length, have free ends. Most of the toughness of the shell comes simply from thickened skin, and these turtles are much more vulnerable to incidental injury than others. Despite their reduced shells, they still have some ability to withdraw their limbs, and some even have flaps of skin that cover their rear legs while withdrawn.
Softshell turtles are highly aquatic species and spend most of their time underwater. They have elongated snouts that allow them to breathe air with minimal exposure, and they also have the capacity to perform gas exchange through their skin as amphibians do.