[5] The coscoroba swan's placement within the family Anatidae is not fully agreed upon, with a 2014 genetic study positing a phylogenetic relationship between this species and the Cape Barren goose (Cereopsis novaehollandiae).

[4] However, the South American Classification Committee of the American Ornithological Society, the International Ornithological Committee (IOC), and the Clements taxonomy treat the Cape Barren goose as basal to other geese, which themselves precede the coscoroba and other swans in a linear sequence.

They have completely feathered faces—unusual for true swans—and their feet are located directly under their bodies, enabling the coscoroba swan to walk more efficiently than the “waddling” of most waterfowl.

[10] The sexes have the same plumage; upon hatching, the chicks have blue-grey bills and feet and black striping running down the length of their bodies (to aid in camouflage from predators), with this eventually fading by about eight months of age.

It also breeds but does not winter from southern Chile and Argentina south to Tierra del Fuego and occasionally to the Falkland Islands.

In winter its range extends north to central Chile, northern Argentina, Paraguay, Uruguay, and southern Brazil.

[1] The species' population varies dramatically at different parts of its range, being fairly common in Argentina, uncommon in Paraguay and Uruguay, rare in Chile, and uncertain in Brazil.

The "[g]reatest threat seems to be loss of temperate marsh habitats due to urbanization and agricultural developments".