Average size :  40 to 48 cm (16 to 19 in), males 621 g (22 oz), females 532 g (19 oz)

Coloration :  2 forms distinguishable mostly by tail color: Reddish-brown form more frequent in the south, cryptic rust-colored plumage, black ruff, tail with rust-colored bars and large, black sub-terminal band; gray form more frequent in the north, cryptic grayish-brown plumage, black ruff, gray tail with large, black sub-terminal band.

External characteristics :  Short, stout beak; small crest; ruff visible during drumming, courtship and when in danger; feathered nares; short, rounded wings; partially feathered feet; fanned tail.