[4] Additional specimens referred to Aetosaurus have been found in the Chinle Group of the southwestern United States,[5][6] and the Fleming Fjord Formation of Greenland.

The lateral scutes, which are beneath the paramedian and formed a row on either side of the animal, do not bear any spikes or other projections.

[4] A 2023 study based on a fossil assemblage found in Kaltental, suggested that juvenile A. ferratus were likely gregarious animals, possibly to increase their chances of survival and to deter predators.

[8][9] Aetosaurus was first named, with the description of the type species A. ferratus, in 1877 by German paleontologist Oscar Fraas.

[14] Stegomus arcuatus was found to be synonymous with Aetosaurus on the basis of several similarities, including a lack of spikes and a distinctive radial pattern of grooves on some of the caudal scutes.

[16] Aetosauroides scagliai Aetosaurus ferratus Coahomasuchus kahleorum Neoaetosauroides engaeus Calyptosuchus wellesi Stagonolepis robertsoni Aetobarbakinoides brasiliensis Typothorax Redondasuchus Tecovasuchus chatterjeei Rioarribasuchus chamaensis Paratypothorax andressorum Sierritasuchus macalpini Longosuchus meadei Lucasuchus hunti Acaenasuchus geoffreyi Desmatosuchus haplocerus Desmatosuchus smalli