[4] In 2003, David Unwin defined a clade Dimorphodontidae, as the group consisting of the last common ancestor of Dimorphodon macronyx and Peteinosaurus zambellii, and all its descendants.

[5] However, later studies found that Dimorphodon may not be closely related to Peteinosaurus, so this definition of Dimorphodontidae would therefore be superfluous.

[6] In 2018, a close relative of Dimorphodon was described from the Late Triassic of North America by Britt and colleagues, and was named Caelestiventus.

This discovery expanded the geographic, temporal and also the ecological range of dimorphodontids, as it was discovered in the Late Triassic Nugget Sandstone in Utah, which was a desert at the time.

Britt and colleagues also redefined Dimorphodontidae as the least inclusive clade containing Dimorphodon macronyx and Caelestiventus hanseni.