Azara's Spinetail

Azara's spinetail is 15 to 18 cm (5.9 to 7.1 in) long and weighs 12 to 18 g (0.42 to 0.63 oz). The sexes have the same plumage. Adults of the nominate subspecies S. a. azarae have a brownish gray face with a slightly paler supercilium. Their forehead and forecrown are dark grayish brown, their hindcrown and nape dark rufous, and their back, rump and uppertail coverts rich olive-brown. Their wings are mostly rufous-chestnut with dark brownish tips on their flight feathers. Their tail is dull chestnut-brown; the tail is graduated and the feathers have somewhat pointed tips. Voice: Azara's spinetail is quite vocal, repeating for minutes at a time a sharp "ket-kwééék", "pip-squeak", or "ka-kweeék". It also makes "scratchy, nasal 'prrt' notes", " 'kweek-kweek' notes", and a "low short 'chur' or 'trrt' ".