Testudinoidea is a

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

within the suborder

Cryptodira The Cryptodira ('' el, hidden neck'') are a suborder of Testudines that includes most living tortoises and turtles. Cryptodira differ from Pleurodira (side-necked turtles) in that they lower their necks and pull the heads straight back into the ...

of the order

Testudines Turtles are an order (biology), order of reptiles known as 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) an ...

. It includes the

pond turtles Emydidae (Latin ''emys'' (freshwater tortoise) + Ancient Greek εἶδος (''eîdos'', “appearance, resemblance”)) is a family of testudines (turtles) that includes close to 50 species in 10 genera. Members of this family are commonly calle ...

(Family: Emydidae), Asian turtles (Family: Geoemydidae), the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

big-headed turtle The big-headed turtle (''Platysternon megacephalum'') is a species of turtle in the family Platysternidae from Southeast Asia and southern China. Background Previously considered a distinct family placed on occasion in " Kinosternoidea", it w ...

(Family: Platysternidae), and the

tortoise Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a turtle shell, shell to protect from predation and other threats. The shell in tortoises is generally hard, ...

s (Family: Testudinidae).

Systematics

A 2021 study found the clade to be divided into two extant groups: Testuguria, containing

Geoemydidae The Geoemydidae (formerly known as Bataguridae) are one of the largest and most diverse families in the order Testudines (turtles), with about 70 species. The family includes the Eurasian pond and river turtles and Neotropical wood turtles. Memb ...

and Testudinidae; and Emysternia, containing

Emydidae Emydidae (Latin ''emys'' (freshwater tortoise) + Ancient Greek εἶδος (''eîdos'', “appearance, resemblance”)) is a family of testudines (turtles) that includes close to 50 species in 10 genera. Members of this family are commonly calle ...

and Platysternidae. The extinct Lindholmemydidae, formerly classified in Testudinoidea, may fall outside the crown group of Testudinoidea, although there is not yet enough evidence for this. * Pantestudinoidea ** Lindholmemydidae? **Testudinoidea ***'' Wutuchelys'' ***

Haichemydidae Haichemydidae is an extinct family of turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side ...

*** Sinochelyidae *** Testuguria ****

**** Testudinidae *** Emysternia ****

**** Platysternidae

References

;Bibliography * {{Turtle-stub