Turtles have been classified in different ways by different authors. While they were previously considered
anapsid
An anapsid is an amniote whose skull lacks one or more skull openings (fenestra, or fossae) near the temples. Traditionally, the Anapsida are the most primitive subclass of amniotes, the ancestral stock from which Synapsida and Diapsida evolve ...
s, they are now considered more derived. Recent analyses of molecular evidence have strongly suggested that they belong in the clade
Archosauromorpha (also known as Archelosauria).
Below are many of the possible classifications of
Testudines
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 necked turtles) and Cryptodira (hidden necked t ...
and
Testudinata:
Thomson and Shaffer, 2010
Below is a cladogram of living testudines found by Thomson and Shaffer in 2010:
Sterli 2010
Below is a cladogram found by Sterli in 2010 in a phylogenetic analysis of Pleurodira:
Joyce, 2007
Below is a cladogram found by Joyce in 2007 in his publication on turtle phylogeny:
See also
Wikipedia category tree of Testudines taxonomy
References
{{Reflist
Testudines
Turtle taxonomy
Testudinata