Genus: Choconsaurus SIMON, SALGADO & CALVO, 2018
Etymology: In reference to the type locality of Villa El Chocon, Neuquen Province, Argentina, where the holotype and type species come from, and Greek, sauros, "lizard."

Species: baileywillisi SIMON, SALGADO & CALVO, 2018
Etymology: In honor of Bailey Willis (1857-1949), a North American geologist who explored the Argentinean Patagonia during the first decades of the 20th century. As a consultant to the National Government of Argentina, Willis carried out multiple productive projects for the Patagonian region, including the utilization of the Limay River for generation of hydraulic energy.
= Genus: Nova? SIMON, 2001, SIMON & CALVO, 2002

Holotype: MMCh-PV 44

Locality: La Antena, 2000 meters away from the main access to Villa El Chocon Town, Confluencia Department, 39°15'24"S, 68°46'49"W, Neuquen Province, Argentina.

Horizon: Lower levels of the Huincul Formation, Rio Limay Subgroup, Neuquen Group.

Biostratigraphy:

Age: Late Cenomanian Stage, Late Gallic Subepoch, Early Gulf Epoch, Middle Cretaceous.

Material:

Breakdown as follows:

MMCh-PV 44/1: ?First dorsal vertebra.

MMCh-PV 44/2: ?Second dorsal vertebra.

MMCh-PV 44/3: ?Third dorsal vertebra.

MMCh-PV 44/4: ?Fourth dorsal vertebra.

MMCh-PV 44/5, 6: ?Sixth dorsal vertebra associated with ?Seventh dorsal vertebrae.

MMCh-PV 44/7-8: ?Eighth dorsal vertebra associated with ?Ninth dorsal vertebrae.

MMCh-PV 44/9: ?Tenth or eleventh dorsal vertebra.

MMCh-PV 44/10: A right scapula and coracoid.

MMCh-PV 44/11: Right sternal plate.

MMCh-PV 244/5-9: Right metacarpus.

Paratype:

MMCh-PV 80: Left premaxilla.

MMCh-PV 81: Right dentary.

MMCh-PV 82, 86: Teeth.

MMCh-PV 83, 87, 88: Maxillary teeth.

MMCh-PV 84, 85: Dentary teeth.

MMCh-PV 89, 90, 91: Anterior/mid-cervical vertebrae.

MMCh-PV 92: Posterior cervical vertebra.

MMCh-PV 93-96: Dorsal rib fragment.

MMCh-PV 97, 98: Anterior caudal vertebrae.

MMCh-PV 99-111: Mid/posterior caudal vertebrae.

MMCh-PV 112: Haemal arch.

MMCh-PV 244/1-4: Mid-caudal vertebrae: