Order Notaspidea Fischer 1883 (snail)
Parent taxon: Opisthobranchia according to J. A. Todd 2001
See also Beesley 1998
Sister taxa: Acanthotrophia, Acochlidea, Buscotypus, Canepina, Cephalaspida, Cephalaspidea, Cylindrobullinoidea, Floribella, Gymnosomata, Heteroptygmatis, Heterostrophia, Lutima, Mariottia, Mistostigma, Nicosiaella, Paronaella, Pseudofusia, Reticulacella, Rhodopemorpha, Scorbinidola, Tectibranchia, Thecosomata, Umbraculomorpha
Subtaxa: Pleurobranchoidea Tylodinoidea
Ecology: epifaunal