Sumatran wren-babbler Napothera albostriata

With its long curved bill, this uncommon Sumatran mountain forest endemic is unique within its limited range. Forages alone or in pairs, often in dense undergrowth where it can be difficult to see; listen for its song, a well-spaced series of even, clipped whistles that sound like they should be coming from a small owl. If lucky enough to catch a glimpse, look for a streaky dark brown body, very short tail, and bright white throat.