Blue-billed Black Tyrant

The blue-billed black tyrant is 14.5 to 15 cm (5.7 to 5.9 in) long. Adult males are almost entirely glossy black but for faint white edges on the underside of their remiges. Adult females have mostly rufous-brown upperparts. Their crown is a brighter rufous, their rump rufous, and their tail coverts bright cinnamon. Their wings are blackish with buff to cinnamon edges on the coverts that show as two wing bars. Their tail is dusky with rufous edges to the feathers. Their underparts are mostly whitish to yellowish white with heavy blackish brown streaks and their crissum is cinnamon-rufous. Voice: The blue-billed black tyrant is not highly vocal. Its call is an "extr. high, staccato whic".