Grey-backed Tachuri

The grey-backed tachuri (Polystictus superciliaris) is a species of bird in subfamily Elaeniinae of family Tyrannidae, the tyrant flycatchers. It is endemic to Brazil. == Taxonomy and systematics == The grey-backed tachuri shares genus Polystictus with the bearded tachuri (P. pectoralis) but several authors have described the relationship as weak and needing confirmation. The grey-backed tachuri is monotypic. == Description == 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. Their chin is whitish. Their throat and underparts are mostly pinkish buff that becomes white on the lower belly. Juveniles have a cream-colored belly. Both sexes have a dark brown…