Grey-backed Tachuri

The grey-backed tachuri is 9.5 to 10 cm (3.7 to 3.9 in) long and weighs about 6 grams (0.21 oz). The sexes have the same plumage. Adults have a gray crown with a short crest; the crown's white center is mostly hidden. They have a short white supercilium, a white eye ring, and a thin blackish line through the eye on a face that is otherwise thinly striped with black and white. Their upperparts are brownish gray. Their wings are dark dusky brown with slightly paler brown edges on the flight feathers and tips on the wing coverts; the last show as two wing bars. Their tail is dusky. Voice: The grey-backed tachuri's song is a "nervous, sustained 'tititi---' interrupted by toneless 'purrrrr' trill". Its call is a "series of thin, compact 'eeh-uk' " notes.