[Kingdom] Animalia Linnaeus, 1758 - animals Grade Enterozoa Grade Cœlomata Phylum Mollusca Linnaeus, 1758 - molluscs Branch Eucephala Grade Echinoglossa Class Gastropoda Cuvier, 1795 - snails and slugs Grade Cochlides Order Natantia Lankester, 1877 Genus Atlanta Lesueur, 1817