Altacreodus

Altacreodus ("creodont from Alberta") is an extinct genus of eutherian mammals. Fossils have been found in North America where they first appeared during the Late Cretaceous, and they died out prior to the start of the Paleocene. It is possibly one of the earliest known placental mammals in the fossil record.

The type species is "Cimolestes" magnus, which was renamed Altacreodus magnus in 2015. Recent phylogenetic analyses suggests that genus Altacreodus is a member of clade Pan-Carnivora and the closest known sister taxon to genus Tinerhodon and the order Hyaenodonta, based on anatomy of its teeth. In some studies its position as a crown-group placental has been equivocal.