Phylum Foraminifera d'Orbigny, 1826 see Subphylum Foraminifera d'Orbigny, 1826 Class Miliolata Saidova, 1981 - porcelaneous foraminifers Subclass Miliamminana Mikhalevich, 1980 Order Schlumbergerinida Mikhalevich, 1980 Family Sigmoilopsidae Vella, 1957 Subfamily Sigmoilopsinae Vella, 1957 1 Genus Sigmoilopsis Finlay, 1947 2 Genus †Silicosigmoilina Cushman & Church, 1929