Skulking and generally inconspicuous brown bird of humid tropical forest. Found as singles or pairs, clambering in vine tangles or other dense understory, at times in leaf litter on the forest floor; usually difficult to see clearly. Note the rich buffy throat, conspicuous buffy eyebrow and eyering, and rusty tail on an otherwise plain dark brownish bird. Song is a descending series of nasal notes, speeding up and often sputtering at the end. Occurs from central Panama (where approaches the range of Fawn-throated Foliage-gleaner, and best distinguished by voice) throughout much of northern South America, to central Brazil.