Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Ornithurae Haeckel, 1866 see Clade Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}
     Infraclass Carinatae Merrem, 1813 see Clade Carinatae Merrem 1813 [Gauthier & de Queiroz 2001]
       Order Pelecaniformes Sharpe, 1891
         1 Suborder Sulae Sharpe see Parvorder Sulida (Reichenbach, 1849) Sibley et al., 1988
         2 Suborder Phaethontes Sharpe, 1891
         3 Suborder †Odontopterygia Spulski see Order Odontopterygiformes Spulski, 1910
         4 Suborder †Cladornithes Wetmore
         5 Suborder Pelecani Sharpe, 1891 see Infraorder Pelecanides Sharpe, 1891
         6 Suborder Fregatae Sharpe see Infraorder Fregatides Sharpe, 1891