Phylum Porifera Grant, 1836 - sponges
   Class Hexactinellida Schmidt, 1870 - hexactinellids
     Subclass Hexasterophora Schulze, 1886
       Order Hexactinosa Schrammen, 1903 see Order Hexactinosida Schrammen, 1903
         Family Euretidae Zittel, 1877
           Subfamily Chonelasmatinae Schrammen, 1912
             1 Genus †Megalodictyon Oppliger, 1926
             2 Genus †Balantionella Schrammen, 1902
             3 Genus †Eubrochis Schrammen, 1902
             4 Genus †Habrosium Schrammen, 1912
             5 Genus †Ptychorete Reid, 1964
             6 Genus †Typhlopleura Schrammen, 1902
             7 Genus †Wollemannia Schrammen, 1912
             8 Genus †Chonelasma Schulze, 1886
             9 Genus †Tretochone Reid, 1958