Genus: Promastodonsaurus BONAPARTE, 1963
Etymology: Greek, pro, "before" + Mastodonsaurus.

Species: bellmanni BONAPARTE, 1963
Etymology:

Holotype: PVL 2092

Locality: Hoyada de Ischigualasto, Valle de la Luna, San Juan Province, Argentina.

Horizon: Ischigualsto Formation.

Biostratigraphy:

Age: Lower Carnian Stage, Late Triassic Epoch, Late Triassic.

Material: Fragmentary skull and fragmentary skeleton.