[Avialae] Gauthier 1986
   Aves Linnaeus 1758 [Gauthier 1986], nom. cl. inval. see Subclass Aves Linnaeus, 1758
     Pygostylia Chatterjee 1997 [Chiappe 2001]
       Ornithothoraces Chiappe 1995
         †Enantiornithes Walker 1981 [Sereno 1998] see Infraclass Enantiornithes Walker, 1981
           1.1 Genus †Neuquenornis Chiappe & Calvo, 1994
           1.2 Genus †Gobipteryx Elżanowski, 1974
           1.3 Genus †Sinornis Sereno & Rao, 1992
           1.4 Genus †Concornis Sanz & Buscalioni, 1992
           1.5 Genus †Eoalulavis Sanz et al., 1996
           2.1 Genus †Noguerornis Lacasa-Ruiz, 1989
           2.2 Genus †Iberomesornis Sanz & Bonaparte, 1992