Trionychia is a superfamily of

turtle Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Crypt ...

s which encompasses the

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

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 The pig-nosed turtle (''Carettochelys insculpta''), also known as the Fly River turtle, the pitted-shelled turtle, and the Warrajan is a species of turtle which is native to northern Australia and southern New Guinea. It is the only living mem ...

(''Carettochelys insculpta'') native to New Guinea and Northern Australia, and

Trionychidae Trionychidae is a family of turtles, commonly known as softshell turtles or simply softshells. The family was described by Leopold Fitzinger in 1826. Softshells include some of the world's largest freshwater turtles, though many can adapt to li ...

, 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 ''Sinaspideretes'' is an extinct genus of turtle from the Late Jurassic of China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the ...

'' from the Late Jurassic of China.

Systematics

Except for those not assigned to a family, only living genera are listed here. *Family Carettochelyidae ** Subfamily Carettochelyinae *** Genus '' Carettochelys'' *Pan-Trionychidae ** Family PlastomenidaeOne or more basal lineages formerly believed to be a distinct family (fossil) ** Family

***Subfamily

Cyclanorbinae Cyclanorbinae, also known commonly as the flapshell turtles, is a subfamily of softshell turtles in the family Trionychidae. The subfamily is native to Africa and Asia. Taxonomy Morphological evidence supports Cyclanorbinae being the sister g ...

**** Genus '' Cyclanorbis'' **** Genus '' Cycloderma'' **** Genus ''

Lissemys ''Lissemys'' is a genus of softshell turtles in the subfamily Cyclanorbinae of the Family (biology), family Trionychidae. The genus is indigenous to southern Asia. Species The genus ''Lissemys'' contains three extant species which are recognize ...

'' *** Subfamily

Trionychinae The Trionychinae are a subfamily of turtles in the family Trionychidae. Classification The subfamily has 11 extant genera: *''Amyda'' *''Apalone'' *''Axestemys'' *''Chitra (turtle), Chitra'' *''Dogania'' *''Drazinderetes'' *''Gobiapalone'' * ...

**** Genus '' Amyda'' **** Genus ''

Apalone ''Apalone'' is a genus of turtles in the family Trionychidae. The three species of ''Apalone'' are native to freshwater habitats in North America; they are the only living softshell turtles from the Americas (other American softshell turtles ar ...

'' **** Genus '' Chitra'' **** Genus ''

Dogania The Malayan softshell turtle (''Dogania subplana'') is a species of softshell turtle in the family Trionychidae. It is monotypic in its genus. Geographic range It is found in Brunei, Indonesia, Java, Kalimantan, Malaysia, Myanmar, the Philippine ...

'' **** Genus '' Nilssonia'' **** Genus '' Palea'' **** Genus ''

Pelochelys ''Pelochelys'' is a genus of very large softshell turtles in the family Trionychidae. They are found from peninsular India northeast to southern China, and south to Southeast Asia and New Guinea.These turtles are also known as Giant softshell tu ...

'' **** Genus '' Pelodiscus'' **** Genus ''

Rafetus ''Rafetus'' is a genus of highly endangered softshell turtles in the family Trionychidae. It is a genus of large turtles which are found in freshwater habitats in Eurasia. Taxonomy Evolution Phylogenetic evidence largely suggests that ''Rafe ...

'' **** Genus '' Trionyx''

References

;Bibliography * {{Taxonbar, from=Q1877590