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
         Suborder †Odontopterygia Spulski see Order Odontopterygiformes Spulski, 1910
           1 Family †Odontopterygidae Lambrecht, 1933
           2 Family †Pseudodontornithidae Lambrecht
           3 Family †Pelagornithidae Fürbringer