Species: chainko CHIMENTO, AGNOLIN, GARCIA-MARSA, MANABE, TSUIHIJI & NOVAS, 2024
Etymology: Aonikenk language, chaink, "large" and Aonikenk language, ko, "bone."

Holotype: MPM-PV-23365

Locality: La Anita Farm, S 50°30'39.888", W 72°33'18.035", Santa Cruz State, Patagonia, Argentina.

Horizon: Close to the same stratigraphic level as teh Isasicursor 2 site, Chorrillo Formation.

Biostratigraphy:

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

Material: Distal end of left ulna, 2 fragmetns of the praecetabular wing of the left ilium, acetabular region of the left hemipelvis, fragment of the ischial blade, proimal end of right femur, distal end of the let femur, proximal end of the tibia and other indeterminate bone fragments.

Referred material:

MPM-PV-23366: Partial left acetabulum and ischium.