Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Mollusca Linnaeus, 1758 - molluscs
     Subphylum Cyrtosoma Runnegar & Pojeta Jr., 1974 see Phylum Mollusca Linnaeus, 1758
       Class Monoplacophora Odhner, 1940 - monoplacophorans
         Order †Bellerophontida Ulrich & Scofield, 1897 see Superfamily Bellerophontoidea McCoy, 1852
           Genus †Bellerophon Montfort, 1808
           Genus †Bucania Hall, 1847
           Genus †Plectonotus Clarke, 1899
           Genus †Sinuites Koken, 1896