Genus: Lamarquesaurus APESTEGUIA & ROUGIER, 2007
Etymology: After the city of Lamarque, Rio Negro Province, Argentina and its inhabitants, who have strongly suported paleontological exploration of northern Patagonia for decades, and Greek, sauros, "lizard."

Species: cabazai APESTEGUIA & ROUGIER, 2007
Etymology: After the Tito Cabaza, amateur paleontologist who discovered the Cerro Tortuga locality and called the attention of professional paleontologists to the region.

Holotype: MML-PV-42

Localityi: 6 m from the base levels of exposures at the "Cerro Tortuga" locailty, 39°26'50"S, 67°19'20"W, Rio Negro Province, Patagonia, Argentina.

Horizon: Lower to middle part of the Allen Formation.

Biostratigraphy:

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

Material: Right maxilla preserving 10 teeth with differnet degrees of completeness.