Sillustania quechuense was named by Crochet and Sigé (1996). Its type specimen is CHU 33, a tooth, and it is a 3D body fossil. Its type locality is Laguna Umayo, Chulpas level, which is in a Thanetian/Ypresian lacustrine conglomerate/sandstone in the Muñani Formation of Peru. It is the type species of Sillustania.