Aetosaurinae currently comprises Aetosaurus, similar forms such as Coahomasuchus and Stenomyti, and the widespread and successful aetosaur clade Typothoracinae.

[1] Aetosaurinae was originally named in 2000, as a subfamily solely including Aetosaurus, which was assumed to be the earliest-diverging aetosaur.

Aetosaurus was recovered as the basal-most stagonolepidid, with other non-typothoracisine aetosaurines placed as successively more derived taxa leading up to a clade containing Desmatosuchinae and Typothoracisinae.

[5][6] More recent data and phylogenies have brought Aetosaurinae back into usage, albeit in a more restricted form.

This also means that the parietals are wider than the frontals on the skull roof, at least in early-diverging genera such as Aetosaurus and Stenomyti.