Phylum Porifera Grant, 1836 - sponges
   Subphylum Hexactinellida Schmidt, 1870 see Class Hexactinellida Schmidt, 1870
     Class Amphidiscophora F.E. von Schulze see Subclass Amphidiscophora Schulze, 1886
       Order Amphidiscosida Schrammen, 1924
         1 Family Hyalonematidae Gray, 1857
         2 Family Pheronematidae Gray, 1870
         3 Family Monorhaphididae Ijima, 1927