Species: irvinensis GAO & FOX, 1991
Etymology:

Holotype: UALVP 29754

Locality: Near Irvine, in S31, Tp11, R2, W4, About 40 km east of Medicine Hat, Cypress County, Southeastern Alberta Province, Canada.

Horizon: Oldman Formation, middle Belly River Group.

Biostratigraphy:

Age: Judithian age, Middle Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material: An anterior part of a right mandible having three complete and ten broken teeth.

Referred material:

GAO & FOX, 1996

UALVP 29757, 29760-29762, 29765-29766, 29768: All Incomplete tooth0bearing dentaries.

Unnumbered dentary fragments.