[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 Genus †Sinornis Sereno & Rao, 1992