Phylum Schizoramia Bergström, 1976a see Phylum Arthropoda Siebold, 1848
   Superclass †Proschizoramia Hou & Bergström, 1997
     Class †Paracrustacea Hou & Bergström, 1997
       Order †Canadaspidida Novozhilov, 1960 see Order Hymenocarina Clarke, 1882
         Family †Hymenocarididae Haeckel, 1896
           Genus †Hymenocaris Salter, 1853
             †Hymenocaris perfecta Walcott, 1912 see Canadaspis perfecta (Walcott, 1912)