Pseudosuchia ("false crocodiles") is one of two major divisions of
Archosauria and includes living
crocodilians and all archosaurs more closely related to crocodilians than to birds (what are often called "crocodilian-line archosaurs"). The name was originally given to a group of superficially crocodile-like prehistoric reptiles from the
Triassic period, but fell out of use in the late 20th century, especially after the name
Crurotarsi was established in 1990 to label the
clade (evolutionary grouping) of archosaurs encompassing most reptiles previously identified as pseudosuchians. By this time, Pseudosuchia had also been defined as a
clade, but it was not widely embraced until 2011, when paleontologist
Sterling Nesbitt proposed that Crurotarsi, as it was originally defined, must include not only crocodilian-line archosaurs, but all other archosaurs including birds,
non-avian dinosaurs, and
pterosaurs. The clade Pseudosuchia as originally defined could still be used to identify crocodilian-line archosaurs, and since many recent studies support Nesbitt's findings, Pseudosuchia is now commonly used.
