Phylum Mollusca Linnaeus, 1758 - molluscs
   Subphylum Conchifera Gegenbauer, 1878
     Class Gastropoda Cuvier, 1795 - snails and slugs
       Subclass Orthogastropoda Ponder & Lindberg, 1995
         Superorder Heterobranchia Burmeister, 1837
           Order Opisthobranchia Milne-Edwards, 1848
             Suborder Thecosomata Blainville, 1824 - shelled pteropods
               1 Family Cavoliniidae Gray, 1850 (1815)
               2 Family Cymbuliidae Gray, 1840
               3 Family Desmopteridae Chun, 1889
               4 Family Limacinidae Gray, 1840
               5 Family Peraclididae Tesch, 1913 see Family Peraclidae Tesch, 1913