Phylum Porifera Grant, 1836 - sponges
   Class Demospongea Sollas, 1875 see Class Demospongiae Sollas, 1885
     Subclass Ceractinomorpha Lévi, 1953 see Class Demospongiae Sollas, 1885
       Order †Sigmatosclerophorida Burton, 1956 [monotypic]
         Family †Dystactospongiidae Miller, 1889
           1 Genus †Dystactospongia Miller, 1883
           2 Genus †Heterospongia Ulrich, 1889
           3 Genus †Loganiella Rigby & Gilland, 1977
           4 Genus †Streptospongia Ulrich, 1889