Genus: Xenotarsosaurus MARTINEZ, GIMENEZ, RODRIGUEZ & BOCHATEY, 1985
Etymology: Greek, xenos, "strange, peculiar," Greek, tarsos, "tarsus" and Greek, sauros, "lizard": "Strange tarsus lizard."

Species: bonapartei MARTINEZ, GIMENEZ, RODRIGUEZ & BOCHATEY, 1985
Etymology: In honor of Jose Bonaparte.

Holotype: UNPSJB-Pv184, UNPSJB-Pv 612

Locality: 6 km north of casco de la ea. "Ocho Hermanos", Department of Sarmiento, Chubut Province, Patagonia, Argentina.

Horizon: Bajo Barreal Formation.

Biostratigraphy:

Age: Late Cretaceous.

Material: 2 dorsal vertebrae, femur, tibia, astragalus and calcaneum.

Referred material:

MARTINEZ, MAURE, OLIVA & LUNA, 1993

Number: Not given: Maxilla.