[Class] Polycystinea Ehrenberg, 1838 - polycystines see Superclass Polycystinia Ehrenberg, 1838 Order Spumellaria Ehrenberg, 1875 see Class Spumellaria Ehrenberg, 1875 Family Spongodiscidae Haeckel, 1862 Genus †Tholodiscus Kozlova, 1972 †Tholodiscus splendens (Ehrenberg, 1875)