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 Passerimorphae Sibley et al., 1988
           Order Ciconiiformes Bonaparte, 1854
             Suborder Ciconii see Suborder Ciconiae Bonaparte, 1854
               Infraorder Ciconiides see Suborder Ciconiae Bonaparte, 1854
                 Parvorder Ciconiida see Suborder Ciconiae Bonaparte, 1854
                   Superfamily Threskiornithoidea Richmond, 1917
                     Family Threskiornithidae Richmond, 1917 - ibises and spoonbills
                       Genus Theristicus Wagler, 1832
                         1 Theristicus caerulescens (Vieillot, 1817) - plumbeous ibis
                         2 Theristicus caudatus (Boddaert, 1783) - buff-necked ibis
                         3 Theristicus branickii Berlepsch & Stolzmann, 1894 - Andean ibis see Theristicus melanopis branickii Berlepsch & Stolzmann, 1894
                         4 Theristicus melanopis (Gmelin, 1789) - black-faced ibis