Genus: Secernosaurus BRETT-SURMAN, 1979
Etymology: Latin, secerno, “sever of divide”, referring to its non-Laurisian origin, and Greek, sauros, “lizard”: “Separated lizard”.

Species: koerneri BRETT-SURMAN, 1979
Etymology: In honor of Dr. Harold E. Koerner, professor emeritus, University of Colorado.

Holotype: FMNH P13423

Locality: 2 miles east of head of Rio Chico, near the Lake Colhue Huapi and to the west of the Gulf of San Jorge, Chubut Province, Patagonia, Argentina.

Horizon: Upper Bajo Barreal Formation (old San Jorge Formation, (?Laguna Palacios Formation, BONAPARTE, 1996)).


Age: Maastrichtian Stage, Upper Senonian Subepoch, Upper Gulf Epoch, Late Cretaceous.

Material: Ilia, prepubis, scapula, fibula, caudals, and partial braincase.