Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795
       Order Neogastropoda Wenz, 1938 see Suborder Neogastropoda Wenz, 1938
         Suborder Stenoglossa Bouvier, 1887
           Superfamily Conoidea Fleming, 1822
             Family Drilliidae Olsson, 1964
               Subfamily Drilliinae Olsson, 1964 see Family Drilliidae Olsson, 1964
                 Genus Horaiclavus Oyama, 1954
                   1 Subgenus Anguloclavus Shuto, 1983
                   2 Subgenus Cytharoclavus Kuroda & Oyama, 1971