Phylum Mollusca Linnaeus, 1758 - molluscs
Class Gastropoda Cuvier, 1795 - snails and slugs
Subclass Opisthobranchia Milne-Edwards, 1848 - opisthobranchs
see Order Opisthobranchia Milne-Edwards, 1848
Order Thecosomata Blainville, 1824 [monotypic] - shelled pteropods
see Suborder Thecosomata Blainville, 1824
Suborder Euthecosomata Meisenheimer, 1905 [monotypic]
see Infraorder Euthecosomata Meisenheimer, 1905
Superfamily Spiratelloidea
see Superfamily Cavolinioidea Gray, 1850 (1815)
1 Family Limacinidae Gray, 1840 [monotypic]
2 Family Cavoliniidae Gray, 1850 (1815)
3 Family Peraclidae Tesch, 1913 [monotypic]
4 Family Cymbuliidae Gray, 1840
5 Family Desmopteridae Chun, 1889 [monotypic]