Species: americanus ESTES & SANCHIZ, 1982
Etymology: In reference to the American occurrence of the genus.

Holotype: UCMP 125827

Locality: UCMP V-5711, Bushy Tailed Blowout, Quarry area includes the floor of a small blowout approximately 10 yards northwest of the highest point on the ridge forming the northeastern side of the blowouts of loc. V-5003, S 1/2, Sec. 20, T37N, R64W, Lance Creek, Powder River Basin, Niobrara County, Wyoming.

Horizon: Lance Formation.

Biostratigraphy:

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

Material: left Ilium.

Referred material:

UCMP 125828, 125829: left and right distal humerial fragments.

 

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, Upper Senonian subepoch, Upper Upper Gulf epoch, Late Cretaceous.

Material:

UCMP 125830: Left ilium.