Phylum Radiolaria Müller, 1858 see Subphylum Radiozoa Cavalier-Smith, 1987
   Superclass Polycystina Ehrenberg, 1838 see Superclass Polycystinia Ehrenberg, 1838
     Class Nassellaria Ehrenberg, 1847
       Order Cyrtidinata Haeckel, 1862
         Superfamily Eucyrtidioidea Ehrenberg, 1847
           Family †Ruesticyrtiidae Kozur & Mostler, 1979
             Genus †Xiphotheca De Wever, 1979, nom. illeg.