Erlianhyus

The holotype of Erlianhyus (IVPP V 28275) was discovered in strata from the Irdin Manha Formation. Its binomial name is derived from the Erlian Basin, in which it was discovered, and the suffix -hyus, which is often applied to bunodont artiodactyls. The species name, primitivus, refers to it bearing relatively primitive features.^[1] Erlianhyus was originally regarded as the sister taxon of a clade containing dichobunids, anthracotheriids and suoids.^[1] In 2023, Yu and colleagues performed a phylogenetic analysis that recovered it in a polytomy with Andrewsarchus and Achaenodon.^[2]

Erlianhyus is known from a partial maxilla that preserves teeth P³–M³. The molars are bunodont and bear weak cristae, similar to entelodontids.^[1] Similarly M¹ in both Erlianhyus and entelodonts lacks lingual cingulum. However, the molars have a large and lingually-positioned metaconule and the postmetaconule crista on M¹ and M² are distinct, suggesting that it does not belong to that clade.^[2]