[Class] Polycystinea Ehrenberg, 1838 - polycystines see Superclass Polycystinia Ehrenberg, 1838 Order Spumellaria Ehrenberg, 1875 see Class Spumellaria Ehrenberg, 1875 Family Spongodiscidae Haeckel, 1862 Genus Spongodiscus Ehrenberg, 1854 †Spongodiscus cruciferus (Clark & Campbell, 1942)