雁亚科亚科

Systematics

Swans (Tribe Cygnini)

Genus Cygnus – true swans: The black-and-yellow-billed swans are sometimes separated in the genus Olor.

• Genus †Afrocygnus (Miocene of North Africa)
• Genus †Annakacygna – short-winged swans (Miocene of Japan)
• Genus †Megalodytes (Miocene of California)
• True geese (Tribe Anserini)
• Genus Anser – grey and white geese
• Genus Branta – black geese (including †B. rhuax, formerly placed in Geochen)
• Unresolved
• Genus Coscoroba – coscoroba swan

These two genera are distinct from other geese and often elevated to a subfamily of their own (Cereopsinae), or alternatively into the shelduck subfamily Tadorninae:

• Tribe Cereopseini
• Genus Cereopsis – Cape Barren goose
• Genus †Cnemiornis – New Zealand geese (prehistoric)

Some enigmatic subfossils of very large goose-like birds from the Hawaiian Islands do not appear to be moa-nalos (goose-sized dabbling ducks) or B. rhuax. They cannot be assigned to any genus living today, though both may be fairly close to Branta:

Very large Hawaiʻian goose, ?Branta sp.

Giant Oʻahu goose, Anatidae sp. et gen. indet.