Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     Infraclass Neoaves Sibley et al., 1988 see Subcohort Neoaves Sibley et al., 1988
       Parvclass Passerae see Superorder Passerimorphae Sibley et al., 1988
         Superorder Apodimorphae see Order Apodiformes Peters, 1940
           Order Apodiformes Peters, 1940 - swifts
             Family Apodidae Hartert, 1897 - swifts
               Genus Hydrochrous nom. null. see Genus Hydrochous Brooke, 1970
                 Hydrochrous gigas (Hartert & Butler, 1901) - waterfall swift see Hydrochous gigas (Hartert & Butler, 1901)