Genus: Notopolytheles GELFO, GOIN & VEGA, 2025
Etymology: Greek, noto, "south", Greek, poly-, "many" and Greek, theles, "protuberance", the last two in reerence to the multiple cusps characteristic of multituberculate teeth.

Species: joelis GELFO, GOIN & VEGA, 2025
Etymology: In honor of Joel Hernan Carino, who discovered the tooth.

Holotype: MPEF-PV 12400

Locality: Some 12 km north of Arroyo Mirasol Chico (Mirasol Chico Steam) and 9 km southf of the provincial road N° 11, Cerro Bosta Area, 42°58'09.0:S, 67°36'08.2"W, Chubut Province, Patagonia, Argentina.

Horizon: Midle section or second facies, La Colonia Formation.

Biostratrigraphy: Alamitian South American Land-Mammal Age.

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

Material: Isolated left M1.