Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Scaphopoda Bronn, 1862 - tusk shells
     Order Gadilida Starobogatov, 1974
       Family Siphonodentaliidae Tryon, 1884 see Subfamily Siphonodentaliinae Tryon, 1884
         1 Genus Siphonodentalium Sars, 1859
         2 Genus Cadulus Philippi, 1844
         3 Genus Dischides Jeffreys, 1867
         4 Genus Pulsellum Stoliczka, 1868
         5 Genus Striocadulus Emerson, 1962
         6 Genus Polyschides Pilsbry & Sharp, 1898