Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
     Infraclass Neoaves Sibley et al., 1988 see Subcohort Neoaves Sibley et al., 1988
       Parvclass Coraciae see Order Coraciiformes Forbes, 1884
         Superorder Bucerotimorphae see Suborder Bucerotes Fürbringer, 1888
           Order Bucerotiformes Fürbringer, 1888 see Infraorder Bucerotides Fürbringer, 1888
             Family Bucerotidae Vigors - hornbills
               Genus Ceratogymna Bonaparte, 1854, nom. nud.
                 1 Ceratogymna bucinator (Temminck, 1824) - trumpeter hornbill see Bycanistes bucinator (Temminck, 1824)
                 2 Ceratogymna fistulator (Cassin, 1850) - piping hornbill see Bycanistes fistulator (Cassin, 1852)
                 3 Ceratogymna brevis (Friedmann, 1929) - silvery-cheeked hornbill see Bycanistes brevis Friedmann, 1929
                 4 Ceratogymna subcylindricus (Sclater, 1870) - black-and-white-casqued hornbill see Bycanistes subcylindricus (P.L. Sclater, 1870)
                 5 Ceratogymna cylindricus (Temminck, 1831) - brown-cheeked hornbill see Bycanistes cylindricus (Temminck, 1831)
                 6 Ceratogymna albotibialis (Cabanis & Reichenow, 1877) - white-thighed hornbill see Bycanistes cylindricus albotibialis (Cabanis & Reichenow, 1877)
                 7 Ceratogymna atrata (Temminck, 1835) - black-casqued hornbill
                 8 Ceratogymna elata (Temminck, 1831) - yellow-casqued hornbill