Phylum Porifera Grant, 1836 - sponges Class Calcarea Bowerbank, 1864 - calcareous sponges Class Demospongiae Sollas, 1885 - demosponges Class Hexactinellida Schmidt, 1870 - hexactinellids Class Sclerospongiae Hartman & Goreau, 1970 see Class Demospongiae Sollas, 1885 Class †Stromatoporoidea Nicholson & Murie, 1878