Phylum Mollusca Linnaeus, 1758 - molluscs
   Conchifera Gegenbaur, 1878 see Subphylum Conchifera Gegenbauer, 1878
     Class Scaphopoda Bronn, 1862 - tusk shells
       Order Gadilida Starobogatov, 1974
         Suborder Gadilimorpha Steiner, 1992
           Family Gadilidae Stoliczka, 1868
             1 Subfamily Gadilinae Stoliczka, 1868
             2 Subfamily Siphonodentaliinae Tryon, 1884
             3 Genus †Calstevenus Yancey, 1973, incertae sedis
             4 Genus †Gadilopsis Woodring, 1925, incertae sedis