living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Eukaryotae see Domain Eukaryota Chatton, 1925
     Kingdom Animalia Linnaeus, 1758 - animals
       Subkingdom Eumetazoa Butschli, 1910 see [unranked] Eumetazoa Bütschli, 1910
         Phylum Cnidaria Hatschek, 1888 - cnidarians
           Class Hydrozoa Owen, 1843
             Order Hydroida Johnston, 1836 - hydroids see Order Anthoathecatae
               Suborder Leptomedusae see Order Leptothecatae
                 01 Family Aequoreidae Eschscholtz, 1829
                 02 Family Bonneviellidae Broch, 1909
                 03 Family Campanulariidae Hincks, 1868
                 04 Family Campanulinidae Hincks, 1868
                 05 Family Clathrozonidae
                 06 Family Dipleurosomatidae Boeck, 1868
                 07 Family Eirenidae Haeckel, 1879
                 08 Family Eucopidae
                 09 Family Eutimidae
                 10 Family Haleciidae Hincks, 1868
                 11 Family Lafoeidae Hincks, 1868
                 12 Family Laodieidae
                 13 Family Lovenellidae Russell, 1953
                 14 Family Melicertidae Agassiz, 1862
                 15 Family Mitrocomidae Haeckel, 1879
                 16 Family Phialellidae Russell, 1953
                 17 Family Phialuciidae Kramp, 1955
                 18 Family Plumulariidae McCrady, 1859
                 19 Family Sertulariidae Lamouroux, 1812
                 20 Family Syntheciidae Marktanner-Turneretscher, 1890
                 21 Family Thyroscyphidae Stechow, 1920 see Family Campanulariidae Hincks, 1868
                 22 Family Timoididae