"nhandumirim" is known from a single partial skeleton, lprp/usp 0651, which includes several vertebrae, a right ilium, and most of a right hindlimb. this skeleton was found at the site of waldsanga (also known as cerro da alemoa or sanga do mato) in santa maria, rio grande do sul. waldsanga is a historically important triassic site which also preserved the type specimens of "saturnalia", "rauisuchus", "gomphodontosuchus", and "alemoatherium". the site preserves carnian-age sediments of the santa maria formation, and lprp/usp 0651 specifically comes from the top of the alemoa member on that site. the generic name "nhandumirim" roughly translates to "small rhea" in the tupi-guarani language. the specific name refers to waldsanga.