Neornithes Gadow, 1893 - living birds
   Neognathae Pycraft 1900 see Cohort Neognathae Pycraft, 1900
     Neoaves Sibley et al. 1988 see Subcohort Neoaves Sibley et al., 1988
       [Order] Passeriformes Linnaeus, 1758
         oscines see Suborder Oscines
           Passerida - passeridans see Parvorder Passerida (C. Linnaeus, 1758) Sibley et al., 1988
             Sylvioidea
               Family Pycnonotidae Gray, 1840 - bulbuls
                 Genus Ixos Temminck, 1825
                   1 Ixos nicobariensis (F. Moore, 1854)
                   2 Ixos mcclellandii (Horsfield, 1840)
                   3 Ixos malaccensis (Blyth, 1845)
                   4 Ixos virescens Temminck, 1825
                   5 Ixos philippinus (J.R. Forster, 1795)
                   6 Ixos rufigularis (Sharpe, 1877)
                   7 Ixos siquijorensis (Steere, 1890)
                   8 Ixos everetti (Tweeddale, 1877)