[Avialae] Gauthier 1986
   Aves Linnaeus 1758 [Gauthier 1986], nom. cl. inval. see Subclass Aves Linnaeus, 1758
     Pygostylia Chatterjee 1997 [Chiappe 2001]
       Ornithothoraces Chiappe 1995
         Ornithuromorpha Chiappe 2001
           1 Genus †Patagopteryx Alvarenga & Bonaparte, 1992
           2 Genus †Vorona Forster et al., 1996
           3 Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}