Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Coelenterata Hatschek, 1888 see Infrakingdom Coelenterata Leuckart, 1847
         Phylum Cnidaria Hatschek, 1888 - cnidarians
           Class Hydrozoa Owen, 1843
             Order Athecata see Order Anthoathecatae
               01 Family Corynidae Johnston, 1836
               02 Family Pennariidae McCrady, 1859
               03 Family Milleporidae Fleming, 1828
               04 Family Branchiocerianthidae see Family Corymorphidae Allman, 1872
               05 Family Tubulariidae Goldfuss, 1818
               06 Family Margelopsidae Mayer, 1910
               07 Family Cladonemidae see Family Cladonematidae Gegenbaur, 1857
               08 Family Eleutheriidae
               09 Family Clavidae McCrady, 1859
               10 Family Hydractiniidae L. Agassiz, 1862
               11 Family Rathkeidae Russell, 1953
               12 Family Bougainvilliidae Lütken, 1850
               13 Family Pandeidae Haeckel, 1879
               14 Family Stylasteridae Gray, 1847
               15 Family Eudendriidae L. Agassiz, 1862