Guatemalan Tyrannulet

The Guatemalan tyrannulet is 10 to 12 cm (3.9 to 4.7 in) long. The sexes have the same plumage. Adults have a grayish crown and a short whitish supercilium. Their upperparts are olive green. Their wings and tail are mostly olive green with yellow edges on the wing coverts, flight feathers, and tail feathers. Their underparts are mostly off-white with faint darker streaks on the breast and sometimes a pale yellow wash on the belly and undertail coverts. Both sexes have a light brown or brownish black iris, a short brownish black bill, and long brownish black legs and feet. Voice: The Guatemalan tyrannulet's call is "a clear, slightly ringing to plaintive peeu or pyeu". It is assumed to have a dawn song like that of the mistletoe tyrannulet's, which is "a series of notes, the first a slow, dropping syllable and the rest short and rising...yer-de-dee, often followed by a trill".