Genus: Malefica PRIETO-MARQUEZ & WAGNER, 2023
Etymology: Latin, feminine, maleficus, “switch or sorceress”, in reference to the toponym of the type locality, 'gruja' being Spanish for witch.

Species: deckerti PRIETO-MARQUEZ & WAGNER, 2023
Etymology: In honor of Frank Deckert, former superintendent (2001-2003) of Big Bend National Park, who collected the type and only known specimen.
= Kritosaurus sp DAVIS, 1983

Holotype: TxVP 41917-1 (old Texas Memorial Museum 41917-1)

Locality: Near Bruja Canyon (misspelt Bruta Canyon in Wagner 2001), a deep, narrow chasm carved into- and subparallel to the Santa Elena Escarpment at the westernmost edge of Big Bend Nationa l Park, on flats east of Mesa de Anguila north of the abandoned village of Terilingua Abajo and south of Sierra Aguja, located at about 29’12’N, 103’38”W, on Mesa de Anguila 7.5’ Topographic Quadrangle, Big Bend National Park, Brewseter County, Texas.

Horizon: Second unit of the upper Shale Member, Aguja Formation.
Note: Equivalent to the Lower Oldman Formation.

Biostratigraphy:

Age: Judithian age, Upper Campanian Stage, Senonian subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Partial left maxilla.