Brown-billed scythebill

The brown-billed scythebill (Campylorhamphus pusillus) is a species of bird in the subfamily Dendrocolaptinae of the ovenbird family Furnariidae. It is found in Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela.

The brown-billed scythebill is 20 to 25 cm (7.9 to 9.8 in) long and weighs 32 to 48 g (1.1 to 1.7 oz). It is a slim, medium-sized woodcreeper with a very long, slim, dramatically decurved bill. The sexes have the same plumage. Adults of the nominate subspecies have a face and neck streaked buff and blackish brown, with a faint buffy supercilium. Their crown and nape are dark brown, with thin deep buff streaks that extend sparsely onto the upper back. Their back and wing coverts are deep reddish brown, their rump is cinnamon-rufous, and their wings and tail are rufous-chestnut. Their primaries have grayish brown edges and dusky tips. Their throat is deep buff with dusky streaks. Their underparts are dark brown to olive-brown that becomes more rufescent on the lower belly and undertail coverts. Their lower neck, breast, and upper belly have thin deep buff streaks; their undertail coverts have lighter buff streaks. Their underwing coverts are cinnamon-buff to ochraceous. Their iris is dark brown to cinnamon-brown, their bill blackish brown to brownish horn, and their legs and feet olive-green to blackish brown. Juveniles are darker and more olivaceous than adults, with wider deeper buff but less distinct streaks, and a shorter and darker bill.

The other subspecies of the brown-billed scythebill differ from the nominate and each other thus:

C. p. borealis, darker overall than nominate, more blackish crown, more olive underparts, narrower but more extensive and deeper buff streaks above and below, wings and tail deeper chestnut, and darker maxilla

C. p. olivaceus, smaller and darker than borealis with black crown, deeper brown back and more olive underparts

C. p. tachirensis, more olive than nominate, especially on underparts

C. p. guapiensis, smaller than nominate, more brownish, ochraceous streaking only on crown, nape, breast, and upper belly