Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758 Subclass †Sauriurae Haeckel, 1866 see Subclass Archaeornithes Gadow, 1893 Infraclass †Enantiornithes Walker, 1981 Order †Alexornithiformes Brodkorb, 1976 Family †Enantiornithidae Nessov & Borkin, 1983 Genus †Avisaurus Brett-Surman & Paul, 1985