Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates
             Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
               Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
                 Order Falconiformes Sharpe, 1874
                   Family Accipitridae Vieillot, 1816 - secretary bird, osprey, kites, hawks and eagles
                     Subfamily Circinae Sundevall, 1836 - harriers see Subfamily Accipitrinae Vieillot, 1816
                       Genus Circus Lacépède, 1799
                         1 Circus cyaneus (Linnaeus, 1766) - northern harrier
                         2 Circus pygargus (Linnaeus, 1758) - Montagu's harrier
                         3 Circus macrourus (Gmelin, 1770) - pallid harrier
                         4 Circus melanoleucus (Pennant, 1769) see Circus melanoleucos (Pennant, 1769)
                         5 Circus aeruginosus (Linnaeus, 1758) - western marsh-harrier
                         6 [Circus maillardi] Verreaux, 1862 - Madagascar marsh-harrier