living organisms
 see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
  
 Superkingdom Eukaryotae
 see Domain Eukaryota Chatton, 1925
    
 Kingdom Animalia Linnaeus, 1758 - animals
      
 Subkingdom Eumetazoa Butschli, 1910
 see [unranked] Eumetazoa Bütschli, 1910
        
 Phylum Mollusca Linnaeus, 1758 - molluscs
          
 Class Gastropoda Cuvier, 1795 - snails and slugs
            
 Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs
 see Class Gastropoda Cuvier, 1795
              
 Order Mesogastropoda Thiele, 1925 - mesogastropods
 see [unranked] mesogastropods
                
 Superfamily Cypraeacea
 see Superfamily Cypraeoidea Rafinesque, 1815
                  
 Family Ovulidae Fleming, 1822 - egg snails
                    
 1 Genus Ovula Bruguière, 1789
                    
 2 Genus Simnia Risso, 1826
                    
 3 Genus Volva Röding, 1798
                    
 4 Genus Cyphoma Röding, 1798