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Term to be defined Definition Synonyms & Keywords
Stiff-tails This Waterfowl group is presently recognized to contain all members of the genera Oxyura, and Biziura lobata - Musk duck. (See List of waterfowl species). This group are Diving ducks which have an unusually stiff tail which is frequently carried erect.

Heteronetta atricapilla - Black-headed duck is frequently included in the group, although it may not be closely related taxonomically. (B25, V.w5, V.w6,)