Comb Duck

Overview

The comb duck or American comb duck (Sarkidiornis sylvicola), is an unusual duck found in tropical wetlands in continental South America south to the Paraguay River region in eastern Paraguay, southeastern Brazil and extreme northeastern Argentina, and as a vagrant on Trinidad.
Most taxonomic authorities split this species and the knob-billed duck from each other. The comb duck is generally smaller in size when compared to the knob-billed duck, and flanks are darker (black in males, medium grey in females).

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