Genus: Paleomolops CIFELLI, 1994
Etymology: Greek, paleo, "ancient", old rogue, allusioni both to the pre-Cenozoic age of the genus, and the difficulty of classifying it.

Species: langstoni CIFELLI, 1994
Etymology: In honor of Wann Langston. Jr., in recognition of his contributions to knowledge of fossil vertebrates from the Big Bend, through field investigations spanning more than 50 years.

Holotype: OMNH 22789

Locality: Terlingua local fauna, OMNH V58 (TMM 43057), 8 km NNE Study Butte, Brewster County, Big Bend of the Rio Grande, Brewster County, Texas.

Horizon: Basal upper shale member, Aguja Formation.

Biostratigraphy:

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

Material: Right lower molar, probably the last in the tooth row.

Hypodigm:

OMNH 22786: Right m last? With apex of protoconid broken.

OMNH 23027: Left m, with broken paraconid.

OMNH 25161: Left m.

OMNH 25162: Left mx.

OMNH 25174: Right mx.

OMNH 25182: Right Mx.

Two upper molars, described below, are tentatively referred to the species but are formerly excluded from the hypodigm.