Genus: Kaikaifilusaurus SIMON & KELLNER, 2005
Etymology: From the divinity Kaikai filu of the Mapuce culture (indigenous inhabitants of southern Argentina and Chile), and Greek, sauros, "lizard."

Species: calvoi SIMON & KELLNER, 2005
Etymology: In honor of the paleontologist Jorge Orlando Calvo (Comahue University, Neuquen), who greatly contributed to the development of vertebrate paleontology in the Neuquen Province.

Holotype: MPCHv 4

Locality: Araceli site, located close to the national route 237, near the El Chocon Village, about 80km southeast of the Neuquen City, Neuquen Province, Patagonia, Argentina.

Horizon: Candeleros Formation.

Biostratigraphy:

Age: Early Cenomanian Stage, Upper Gallic subepoch, Lowest Gulf Epoch, Late Early to Early Middle Cretaceous.

Material: Left lower jaw.

Paratype:

MPCHv 5: Right lower jaw lacking the symphyseal and posterior regions.

Note: MN 6767-V: Cast.

Referred material:

APESTEGUIA & NOVAS, 2003

Locality: "Al Buitreta" fossil quarry, Cerro Policia, Rio Negro Province, Argentina.

Horizon: Candeleros Formation.

Biostratigraphy:

Age: Early Cenomanian Stage, Upper Gallic subepoch, Lowest Gulf Epoch, Late Early to Early Middle Cretaceous.

Material:

MPCA 300: A juvenile incomplete skeleton.

MPCA 302: Postcranial isolated remains.

MPCA 303: A partially articulated adult skeleton.