Genus: Sarmientosaurus MARTINEZ, LAMANNA, NOVAS, RIDGELY, CASAL, MARTINEZ, VITA, & WITMER, 2016
Etymology: In reference to Sarmiento, for the Patagonian town and the administrative department in which it is located, the latter of which has yielded numerous Cretaceous dinosaur fossils; and Greek, sauros, "lizard."

Species: musacchioi MARTINEZ, LAMANNA, NOVAS, RIDGELY, CASAL, MARTINEZ, VITA, & WITMER, 2016
Etymology: In honor of the late Dr. Eduardo Musacchio, a model scientist and educator at the Universidad Nacional de la Patagonia San Juan Bosco in Comodoro Rivadavia, Argentina.

Holotype: MDT-PV 2

Locality: Estancia Laguna Palacios, Sierra Nevada Anticline, Golfo San Jorge Basin, south-central Cubut Province, Central Patagonia, Argentina.

Horizon: Upper section of the Lower Member, Bajo Bareal Formation, Chubut Group.

Biostratigraphy:

Age: Cenomanian Stage, Upper Gallic Subepoch, Lowermost Gulf Epoch, Middle Cretaceous­-Turonian Stage, upper Gallic subepoch, lower Gulf Epoch, Early Late Cretaceous.

 Material: Nearly complete skull, the partial axis associated with its rib from the right side and articulated with the cranial part of the third vertebrae, a fragment of the fifth cervical vertebra, the nearly complete sixth cervical vertebra and its rigth rib, the partial seventh cervical vertebra, and a section of ossified cervical tendon.