Phylum Porifera Grant, 1836 - sponges
   Class Hexactinellida Schmidt, 1870 - hexactinellids
     Subclass Hexasterophora Schulze, 1886
       Order Lychniscosa Schrammen, 1903 see Order Lychniscosida Schrammen, 1903
         Family †Calyptrellidae Schrammen, 1912 [monotypic]
         Family Callodictyonidae Zittel, 1878
         Family †Coeloptychidae Roemer, 1864
         Family †Camerospongiidae Schrammen, 1912
         Family †Polyblastidiidae Schrammen, 1912
         Family Dactylocalycidae Gray, 1867
         Family †Sporadopylidae Schrammen, 1936
         Family †Pachyteichismatidae Schrammen, 1936
         Family †Cypelliidae Schrammen, 1936
         Genus †Cavispongia Quenstedt, 1877
         Genus †Plectascus Schrammen, 1912
         Genus †Sclerokalia Hinde, 1883
         Genus †Sestrocladia Hinde, 1883
         Genus †Xylospongia Hérenger, 1942, nom. illeg.
         Family †Ventriculitidae Smith, 1847
           1 Subfamily †Ventriculitinae Smith, 1847
           2 Subfamily †Bolitesiinae Schrammen, 1912 [monotypic]
           3 Subfamily †Stauronematinae Sollas, 1877 [monotypic]
           4 Subfamily †Lychniscaulinae Reid, 2004