About Syndactyla rufosuperciliata (Lafresnaye, 1832)
The buff-browed foliage-gleaner, scientifically named Syndactyla rufosuperciliata, is 17 to 18 cm (6.7 to 7.1 in) long and weighs 22 to 33 g (0.78 to 1.2 oz). It is a medium-sized furnariid with a thick, slightly upcurved bill. The sexes of this species have identical plumage. Adults of the nominate subspecies S. r. rufosuperciliata have a tawny-buff eye ring and a lighter supercilium that extends to the nape; the rest of their face is brownish with small buff markings. Their crown is dull olive-brown with vague whitish streaks at the rear, and their back, rump, and uppertail coverts are plain olive-brown. Their tail is dull rufous and their wings are rich olivaceous brown. Their throat is whitish with some brownish feather tips, their breast is buffy whitish with olive-brown feather edges that create a scalloped appearance, their belly is olive-brownish with wide blurry buffy-whitish streaks that disappear toward the rear, their flanks are a darker olive-brownish with fewer streaks, and their undertail coverts are olive-brownish with ochraceous-tinged streaks. Their iris is brown to dark brown, their maxilla is brown to black, their mandible is whitish to blue-gray, and their legs and feet are olive to brownish gray. Juveniles are similar to adults but have spotted rather than streaked underparts. Subspecies S. r. acrita has a slightly paler supercilium than the nominate, with browner and more olivaceous upperparts, a more chestnut tail, and more prominent belly streaking. S. r. oleaginea has more olivaceous brown underparts than the nominate, and its underpart streaks are thinner and longer. Compared to the nominate, S. r. cabanisi has a richer ochraceous supercilium, a darker crown, a richer brown back, a chestnut wash on the uppertail coverts, a more buff-tinged throat, and richer, more ochraceous underparts with tawny-buff streaking.
This species has a disjunct distribution with two widely separated ranges, and its subspecies occupy distinct areas: S. r. cabanisi ranges from the Cordillera del Cóndor in extreme southern Ecuador south along the east slope of the Andes through Peru into Bolivia; S. r. oleaginea occupies the Andes from central Bolivia south into northwestern Argentina as far as La Rioja Province; S. r. rufosuperciliata occurs in southeastern Brazil from Minas Gerais and Espírito Santo south to Paraná; and S. r. acrita is found in north-central Paraguay, the far southeastern Brazilian states of Santa Catarina and Rio Grande do Sul, Uruguay, and northeastern Argentina south to Buenos Aires Province. Andean populations of the buff-browed foliage-gleaner live in montane evergreen forest and mature secondary forest, often with Chusquea bamboo, between elevations of 1,300 and 2,500 m (4,300 and 8,200 ft); in Bolivia, the species occurs locally as low as 1,000 m (3,300 ft). Southeastern populations inhabit lowland tropical evergreen forest, gallery forest, and secondary forest at elevations up to 2,000 m (6,600 ft).
