Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates
             Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
               Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
                 Order Coraciiformes Forbes, 1884 - rollerlike birds
                   Family Bucerotidae Vigors - hornbills
                     01 Genus Tockus Lesson, 1830
                     02 Genus Ceratogymna Bonaparte, 1854, nom. nud.
                     03 Genus Bycanistes Cabanis & Heine, 1859-1860[1860]
                     04 Genus Berenicornis Bonaparte, 1850
                     05 Genus Aceros Hodgson, 1844
                     06 Genus Ptilolaemus Ogilvie-Grant, 1892 see Genus Anorrhinus Reichenbach, 1849
                     07 Genus Penelopides Reichenbach, 1849
                     08 Genus Rhyticeros Reichenbach, 1849
                     09 Genus Buceros Linnaeus, 1758
                     10 Genus Rhinoplax Gloger, 1841
                     11 Genus Bucorvus Lesson, 1830