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 Arthropoda Siebold, 1848 - arthropods
           Subphylum Chelicerata Heymons, 1901
             Class Pycnogonida Latreille, 1810 - pycnogonids
               Family Pycnogonidae Wilson, 1878
                 Genus Pycnogonum Brünnich, 1764
                   1 Pycnogonum stearnsi Ives, 1892
                   2 Pycnogonum rhinoceros (preoccupied)