Phylum Porifera Grant, 1836 - sponges
   Class Demospongea Sollas, 1875 see Class Demospongiae Sollas, 1885
     Subclass Ceractinomorpha Lévi, 1953 see Class Demospongiae Sollas, 1885
       Order Poecilosclerida Topsent, 1928
         Family Myxillidae Lundbeck, 1905
           1 Genus †Iophon Gray, 1867
           2 Genus †Myxilla Schmidt, 1862
           3 Genus †Iophonopsis Dendy, 1924 see Genus Iophon Gray, 1867