[Class] Polycystinea Ehrenberg, 1838 - polycystines see Superclass Polycystinia Ehrenberg, 1838
   Order Spumellaria Ehrenberg, 1875 see Class Spumellaria Ehrenberg, 1875
     Family Spongodiscidae Haeckel, 1862
       Genus †Rhopalastrum Ehrenberg, 1847
         1 †Rhopalastrum abyssorum (Ehrenberg, 1872)
         2 †Rhopalastrum angulatum (Ehrenberg, 1872)
         3 †Rhopalastrum oraculibrachium Caulet, 1986