Eumetazoa Bütschli, 1910 - eumetazoans
   [unranked] Bilateria Hatschek, 1888 see Subkingdom Bilateria Hatschek, 1888
     Protostomia Grobben, 1908 see Infrakingdom Protostomia Grobben, 1908
       Grade Acoelomates Hyman, 1951
         1 Phylum Platyhelminthes Gegenbaur, 1859 - flatworms
         2 Phylum Nemertea Schultze, 1851 - ribbon worms