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.

References

1. Boreoeutheria
2. Ferae
3. Hyaenodonta
4. Hyaenodon
5. Simbakubwa
6. Sarkastodon
7. Carnivoramorpha
8. Megistotherium
9. Oxyaenidae
10. Creodonta
11. Paleobiota of the Hell Creek Formation
12. Cimolestes
13. Lycophocyon
14. Patriofelis
15. Dissopsalis
16. Dormaalocyon
17. Machaeroidinae
18. Miacis
19. Hyaenodontinae
20. Sinopa