Phylum Porifera Grant, 1836 - sponges Class Demospongea Sollas, 1875 see Class Demospongiae Sollas, 1885 Subclass Choristida Sollas, 1880 see Order Tetractinellida Marshall, 1876 Order Plakinida Reid, 1968 see Order Homosclerophorida Dendy, 1905 Family Plakinidae Schulze, 1880 Genus †Acanthoplakina Burton, 1959