Genus: Mimatuta VAN VALEN, 1978
Etymology: Sindarin (Elvish in Tolkien’s books), mir, “jewel”, and Matuta, Roman goddess of dawn.

Species: morgoth VAN VALEN, 1978
Etymology:

Holotype: UMVP 1560

Locality: Harbicht Hill, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material: Right maxilla with UM2.

Referred material:

ARCHIBALD, 1982

Locality: V73098, Rick's Place, Garfield County, Montana.

Horizon: Hell Creek Formation.

Biostratigraphy:

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

Material:

UCMP Number not given: Dentary with fragment of LM2.