Genus: Tatankaceratops OTT & LARSON, 2010
Etymology: "Tatanka": Lakota Sioux word for the American Bison (Bison Bison), in reference to this specimen being roughtly the size of an Americna Bison, its loclaity being very close to the town of Buffalo, South Dakota, and to recognize and honor the Lakota Sioux Tribe, who are the prior inhabitants of this area, and Latinze Greek, ceratops, 'horned face."

Species: sacrisonorum OTT & LARSON, 2010
Etymology: In honor of Stan and Steven Sacrison, the twin brothers from Buffalo, South Dakota, who discovered and collected the specimen.

Holotype: BHI -6226

Locality: Niemi Ranch, Northwestern South Dakota, approximately 10 miles northnorthwest of the Town of Buffalo, Harding County, South Dakota.

Note: Percise locality data is available from Black Hills Institute upon request.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material: Fragmentary skull and partial skeleton.

Referred material:

BHI-6271: Postorbital of an adult.

BHI-4954: Postorbital.