Diegoaelurus, Zack & Poust & Wagner, 2022

Zack, Shawn P., Poust, Ashley W. & Wagner, Hugh, 2022, Diegoaelurus, a new machaeroidine (Oxyaenidae) from the Santiago Formation (late Uintan) of southern California and the relationships of Machaeroidinae, the oldest group of sabertooth mammals, PeerJ 10, pp. 1-27 : 5-6

DIEGOAELURUS gen. nov.

urn:lsid:zoobank.org:act:2BE5B4DE-1808-44C4-BF56-89090012ACE6

Type Species. Diegoaelurus vanvalkenburghae sp. nov.

Diagnosis. Autapomorphies of Diegoaelurus are loss of p1; p2 single, rather than doublerooted; presence of a paraconid on p3; and a relatively deep mandibular flange.

Differential Diagnosis. Differs from Machaeroides in lacking metaconids on m1-2 and in having lower, more elongate trigonids on m1-2. Differs from Apataelurus in having the mandibular flange only extend back to the level of p2, a relatively larger p3, m2 only moderately larger than m1, and coronoid process taller than m2.

Etymology. Diego, for San Diego, California and Gr. - aelurus, cat. While - ailurus is more frequently used as a combining form, - aelurus is used to align with the closely related Apataelurus .

Comments. In the phylogenetic analysis presented below, Diegoaelurus is recovered as the sister taxon of Apataelurus , raising the question of why D. vanvalkenburghae is placed in a new genus rather than Apataelurus . There are substantial differences in the morphology of the limited overlapping material of D. vanvalkenburghae and species of Apataelurus . Some of the contrasts, particularly the more expansive mandibular flange in Apataelurus , suggest substantial differences in the ecology of the two genera. Additionally, the synapomorphies uniting D. vanvalkenburghae with Apataelurus describe loss of lower molar metaconids and entocristids, both features that have independently evolved numerous times in the evolution of hypercarnivorous mammals. Given the strong homoplastic tendencies in these traits, support for monophyly of Diegoaelurus plus Apataelurus should be considered weak, requiring confirmation from additional material of one or both taxa.