White-crested Tyrannulet

The white-crested tyrannulet is 11 cm (4.3 in) long and weighs 6 to 8.6 g (0.21 to 0.30 oz). The sexes have the same plumage. Adults of the nominate subspecies have a gray crown and nape with white central crown feathers that are usually hidden but sometimes raised as a crest. They have a thin white supercilium, a white partial eye-ring, and a dusky line through the eye on an otherwise grayish white face. Their upperparts are grayish olive. Their wings are dusky to blackish with pale buffy edges to most of the flight feathers and two whitish to pale buffy wing bars. Voice: The white-crested tyrannulet's song differs somewhat among the subspecies. That of the nominate is described as an "almost mechanical-sounding trill with few introductory rising notes, psee psee psee-e-e-e-e-e-e". It also makes a "slower, bubbly tweetweetweetweetweetwee, and occasionally other, more jumbled chatters". The song of S. s.