Trionychia

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 (Carettochelys insculpta) 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.

Carettochelyidae is a family of cryptodiran turtles belonging to the Trionychia. It contains only a single living species, the pig-nosed turtle (Carettochelys insculpta) native to New Guinea and Northern Australia. Stem-group carettochelyids are known from the Cretaceous of Asia, with the family being widely distributed across North America, Europe, Asia and Africa during much of the Cenozoic.

The Adocidae are an extinct family of aquatic and omnivorous turtles. They are freshwater cryptodiran turtles and are mainly known from Cretaceous and Paleogene Asia and North America.

Adocus is an extinct genus of aquatic turtles belonging to the family Adocidae.