[2] The synapomorphies alleged to distinguish the Aublysodontinae, especially lack of serrations on premaxillary teeth could have been caused by tooth wear in life, postmortem abrasion, or digestion.

In 1856 Joseph Leidy had named fourteen teeth collected by Ferdinand Vandeveer Hayden in 1854 and 1855 from the Judith River Badlands of Montana[1] as the species Deinodon horridus.

It is possible the genus name is derived from Greek αὖ, au, "again", "backwards", "contrariwise", βλύζω, blyzo, "to spout", "to flow" and ὀδών, odon, "tooth".

Because of the presence of Aublysodon-type teeth in other juvenile tyrannosaurines than Daspletosaurus, such as those of Tyrannosaurus, remains of which can also be found in Montana, Thomas Carr no longer considered the name to represent a real biological taxon, but to be a nomen dubium.

[21] The skull, specimen LACM 28741 at forty-five centimetres the length of an average human arm, bore pointed teeth attached to a long narrow snout.

[citation needed] It was made a separate genus Stygivenator by George Olshevsky in 1995,[23] but was later, in 2004, reinterpreted to be a juvenile Tyrannosaurus rex by Thomas Carr and Tom Williamson.

[12] Another partial skeleton from New Mexico, specimen OMNH 10131, was in 1990 considered to represent Aublysodon,[24] but later research by Thomas Carr and Tom Williamson first referred it to Daspletosaurus[12] and ultimately to Bistahieversor.

Marsh however, in 1892 was misled by the small size of the teeth, their D-shaped cross-section and their lack of serrations into considering Aublysodon a mammal exceptionally large for the Cretaceous.

[8] By the early twentieth century it was again generally understood that Aublysodon was a theropod reptile; later it would be typically assigned to the Deinodontidae, a group today called the Tyrannosauridae.

[28] This was a concept which afterwards enjoyed some popularity: Thomas Holtz proposed a stem clade definition of the Aublysodontinae in 2001, "Aublysodon and all taxa sharing a more recent common ancestor with it than with Tyrannosaurus".

Because Aublysodon is today considered a nomen dubium based on material probably belonging to Daspletosaurus, its affiliations are likely tyrannosaurid and the terms Aublysodontinae and Aublysodontidae have become irrelevant.