Holotype:

Locality: Maurice Williams’s Ranch, Cheyenne River Indian Reservation, near Faith, Hill City, South Dakota.

Horizon: Hell Creek Formation.

Biostratigraphy:

Age: Lancian age, upper Maastrichtian Stage, uppermost Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Fragmentary skull.

After SULLIVAN, 2006