The screamers are three South American bird species placed in family Anhimidae. They were thought to be related to the Galliformes because of similar bills, but are more closely related to the family Anatidae, i.e. ducks and allies, and the magpie goose, within the clade Anseriformes. The clade is exceptional within the living birds in lacking uncinate processes of ribs. The three species are: The horned screamer (Anhima cornuta); the southern screamer or crested screamer (Chauna torquata); and the northern screamer or black-necked screamer (Chauna chavaria).

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