Neornithes Gadow, 1893 - living birds
   Neognathae Pycraft 1900 see Cohort Neognathae Pycraft, 1900
     Galloanserae Sibley, Ahlquist & Monroe Jr., 1988 see Subcohort Galloanserae Sibley, Ahlquist & Monroe Jr., 1988
       [Order] Anseriformes Wagler, 1831 - waterfowl and screamers
         Family Anatidae Vigors, 1825 - ducks, geese, swans
           Subfamily Anserinae Vigors, 1825 - geese
             Genus Cygnus Bechstein, 1803 - mute swan
               1 Cygnus atratus (Latham, 1790) - black swan
               2 Cygnus melancoryphus (Molina, 1782) - black-necked swan
               3 Cygnus olor (Gmelin, 1789) - mute swan
               4 Cygnus buccinator Richardson, 1831 - trumpeter swan
               5 Cygnus columbianus (Ord, 1815) - tundra swan
               6 Cygnus cygnus (Linnaeus, 1758) - whooper swan