Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Porifera Grant, 1836 - sponges
     Class Demospongiae Sollas, 1885 - demosponges
       Order "Lithistida" Schmidt, 1870 [polyphyletic] - lithistids see Subclass Lithistida Schmidt, 1870
         01 Family Azoricidae Sollas, 1888
         02 Family Corallistidae Sollas, 1888
         03 Family Desmanthidae Topsent, 1893
         04 Family Isoraphinidae Schrammen, 1924 [monotypic] see Family Isoraphiniidae Schrammen, 1924
         05 Family Macandrewiidae Gray, 1859 [monotypic]
         06 Family Neopeltidae Sollas, 1888
         07 Family Phymaraphiniidae Schrammen, 1910
         08 Family Phymatellidae Schrammen, 1910
         09 Family Pleromidae Sollas, 1888 see Family Pleromatidae Sollas, 1888
         10 Family Scleritodermidae Sollas, 1888 see Family Scleritodermatidae Sollas, 1888
         11 Family Siphonidiidae Lendenfeld, 1903
         12 Family Theonellidae Lendenfeld, 1903
         13 Family Vetulinidae Lendenfeld, 1903 [monotypic]