Phylum Porifera Grant, 1836 - sponges Class Demospongea Sollas, 1875 see Class Demospongiae Sollas, 1885 Subclass †Lithistida Schmidt, 1870 Order Tetralithistida Lagneau-Hérenger, 1962 Suborder Tetracladina Zittel, 1878 Family †Phymaraphiniidae Schrammen, 1910 Genus †Prokaliapsis Schrammen, 1901 Subgenus †P. (Prokaliapsis) Schrammen, 1901