Anas Linn., Syst. Nat., 10th ed.. i, p. 122 (1758).
Type by mon., Anas platyrhyncha Linn.
In Anas the bill is broad, though not spatulate, and about equal to the head in length, the sides parallel throughout; the nostril is situated about a quarter the length of the bill from the base; the wings are long and pointed and there is a speculum on the base of the outer secondaries ; the tail of eighteen or twenty feathers is moderate and rather pointed; the tarsus is shielded in front and the hind toe has a narrow lobe; the legs are placed rather far back but all the species of this genus can walk well and freely.
The genus is cosmopolitan and is represented in India by two species.
Key to Species.
A. Sexes different; speculum purple-blue; no white on outer webs of inner secondaries………… A. platyrhyncha, p. 419.
B. Sexes alike; speculum green; outer webs of inner secondaries more or less white………… A. poecilorhyncha, p. 420.