Species: monstrosus LONGRICH, BHULLAR & GAUTHEIR, 2013a
Etymology: Latin, monstrosus, "monstrous."

Holotype: USNM 25870

Locality: Graveyard Coulee, Dawson County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material: Partial right dentary berign 2 teeth.

Referred material:

AMNH 2366: Anterior end of maxilla.

 

Locality: Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

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

Material:

YPM 1063: Parital parietals.

 

Locality: UCMP V-5620, Lull Quarry, near the head of a tributary of Buck Creek, Powder River Basin, Niobrara County (Formerly Converse County), Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

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

Material:

UCMP 49954: Isolated tooth.