Superfamily Sagdoidea Pilsbry 1895 (slug)
Parent taxon: Helicoidei according to P. Bouchet et al. 2017
See also Bouchet et al. 2005
Sister taxon: Helicoidea
Subtaxa: Sagdidae
Ecology: epifaunal
Distribution: found only at Discovery Site (Eocene of Wyoming)