Double-banded Pygmy Tyrant
Lophotriccus vitiosus
The double-banded pygmy tyrant is about 10 cm (3.9 in) long and weighs 6 to 8.5 g (0.21 to 0.30 oz). It has long crown feathers that form a crest and that it occasionally erects and fans; the feathers extend past the back of the head when folded. Females have a smaller crest than males but the sexes otherwise have the same plumage. Adults of the nominate subspecies L. v. vitiosus have a black crest with gray edges on the feathers. They have whitish lores on an otherwise olive face. Their back, rump, and uppertail coverts are olive. Voice: The double-banded pygmy tyrant's song has some regional variation. In Ecuador it is described as "a distinctive short harsh trill that descends in pitch, 'turrrrrrew' ". In Peru, subspecies L. v. vitiosus sings a similarly described "descending, harsh, ringing djzeeer" while L. v. congener sings a "similar, but considerably lower-pitched beerrrrrrp".
ID text from Wikipedia, CC BY-SA 4.0

Scale-crested Pygmy Tyrant
Lophotriccus pileatus
The scale-crested pygmy tyrant is 8 to 10 cm (3.1 to 3.9 in) long and weighs about 7 to 8 g (0.25 to 0.28 oz). It has long crown feathers that form the eponymous crest and that it sometimes erects and fans. Females have a smaller crest than males but the sexes otherwise have the same plumage. Adults of the nominate subspecies L. p. pileatus have a black crest with rufous edges on the feathers. They have whitish lores on an otherwise brownish face. Their back, rump, and uppertail coverts are olive. Voice: The scale-crested pygmy tyrant's main vocalization is a very loud trill that differs somewhat geographically. It has been written as "tr-tr-tr-tr-tr-tr-tr-tr" and "trrrrrreét", "dzzeeer-dzeer-dzeer", and "cre'e'e'e'e, k'e'e'e'e". It also makes "a series of sharp "preek" notes, sometimes widely spaced".
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Double-banded Pygmy Tyrant and Scale-crested Pygmy Tyrant.