Ferruginous duck 
also known as ferruginous pochard, common white-eye or white-eyed pochard
(Vịt mặt trắng, Aythya nyroca), 

The ferruginous duck (Aythya nyroca) is a medium-sized diving duck from Eurosiberia. 

anser: Latin anser goose.
anas, anatis: Latin duck.
Aythya: from the Ancient Greek word authuia, which may have referred to a sea-dwelling duck or an auklet.
nyroca: from nyrok, the Russian name for a duck.

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