Sooty-headed Tyrannulet

The sooty-headed tyrannulet is about 10 cm (3.9 in) long and weighs about 8 g (0.28 oz). The sexes have the same plumage. Adults have a grayish to blackish crown and dull grayish olive nape, back, and rump. Their lores and supercilium are white with a dark stripe through their eye. Their lower face is grizzled. Their wings are dusky with narrow whitish edges to the inner flight feathers and the ends of the coverts. Their tail is dusky. Their throat is grayish white, their breast and flanks pale olive, and their belly bright yellow. Voice: The sooty-headed tyrannulet often sings from an open perch. Its song varies geographically, but in general is "an emphatic phrase of clear, short whistled notes, first one stressed, 'whip, whip-di-irip' or 'whit, whit-wheeu' ".