Trionychoidea

Trionychia is a superfamily of turtles which encompasses the species that are commonly referred to as softshelled turtles as well as some others. The group contains two families, Carettochelyidae, which has only one living species, the pig-nosed turtle native to New Guinea and Northern Australia, and Trionychidae, the softshelled turtles, containing numerous species native to Asia, North America and Africa. These families likely diverged during the late Jurassic. The oldest known stem-trionychian is Sinaspideretes from the Late Jurassic of China.

Wikipedia →