Genus: Aucasaurus CORIA, CHAIPPE & DINGUS, 2002
Etymology: « Auca », from Mapuche language, in reference to Auca Mahuevo, the fossil locality where the specimen was found, and Greek, sauros, « lizard ».

Species: garridoi CORIA, CHIAPPE & DINGUS, 2002
Etymology : In honor of Mr. Alberto Garrido, who discovered the holotype;
= Genus: Nova CORIA, CHIAPPE & DINGUS, 2000

Holotype: MCF-PVPH-236

Locality: Auca Mahuevo, near Mina La Escondida, in the northerastern corner of the Province of Neuquen, northwestern Patagonia, Argentina.

Horizon: Rio Colorado Formation, Anacleto Member.


Age: Campanian Stage, Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material: Skull and nearly complete skeleton.
Note: Traces of soft tissue around the pelvis.
Note: Caudals 5 and 6 are pathologically fused to each other.