Sarkastodon mongoliensis (Granger 1938; AMNH 26641; preserved skull length 37cm; Eocene, 35mya; Fig. 1) was originally considered close to the creodont marsupial, Oxyaena. Here in the large reptile tree (LRT, 1346 taxa, subset Fig. 2) this bear-like carnivore nests in the Carnivora between the wolverine, Gulo, and the seal (Phoca) clade + the Stylinodon clade.
Distinctly the robust nasal of Sarkastodon hangs over the naris, only two robust procumbent premaxillary teeth are present and the multicusp molars have blunt tips, ideal for bone or shell cracking.
Sarkastodon is derived from
wolverines, basal to seals and walruses (Fig. 2).
another similar, but smaller traditional oxyaenid, Patriofelis was added to the LRT, nesting between Gulo and Sarkastodon.
Note the spreading metacarpals and metatarsals
in this taxon (Fig. 4) heading back to the water.
Granger W 1938. A giant oxyaenid from the Upper Eocene of Mongolia. American Museum Novitates 969:1–5.
Leidy J 1873. Contributions to the extinct vertebrate fauna of the Western Territories, Rep. US Geol. Surv. Terr. (Hayden), vol. 1, pt. 1, pp. 7-358 (114-116, 316), pis. 1-37.