Screamers of Anhimidae

The Anseriformes are divided into two families distinguished by the absence or presence of horny lamellae in the beak: (1) screamers (Anhimidae), and (2) ducks and geese (Anatidae).

Anhimidae today only occur in South America and include three species that are distinguished from other anseriform birds in numerous features, including an unspecialized and rather galliform-like beak, the absence of webbed feet, and a highly pneumatized skeleton.

Screamers are a small group of peculiar aquatic birds found only in South America.. They are almost goose-size birds of fowl-like appearance, with fairly thick, long legs and feet without webs. The weight is 2-3 kilograms.

Heavy bodied and superficially gooselike, they have many unusual anatomical features that suggest an ancient lineage. Among other things, they lack feather tracts; the feathers on the head and neck are very short, soft, and downy; and the skin is thick and spongelike.

Screamers take their name from their loud, far-carrying calls. Two sharp, bony spurs project from the bend of each wing. The spurs are used in fighting, either between rival screamers or to drive off enemies, including hunting dogs and other predators.
Screamers of Anhimidae