Spotted Bamboowren Psilorhamphus guttatus Scientific name definitions

The Spotted Bamboowren has enjoyed one of the most turbulent taxonomic histories of any Neotropical bird. While its separate generic status is not in question, Psilorhamphus has been variously placed in the antbirds (Thamnophilidae), wrens (Troglodytidae), and gnatcatchers (Polioptilidae), but skeletal characters and, most recently, genetics have confirmed its placement within the Rhinocryptidae. This species, and genus, is endemic to the Atlantic Forest, where it occurs from southeast Brazil south to extreme northeast Argentina and probably southeast Paraguay. Although its song is quiet, even when the bird is close, and easily overlooked by the inexperienced observer, the species’ highly distinctive vocalizations remain the best means of detecting the Spotted Bamboowren. Despite its name, the Spotted Bamboowren is certainly not confined to patches of bamboo, but is also fond of very dense vine tangles. Pairs often maintain reasonably close contact. Because of the Spotted Bamboowren’s skulking behavior, there is still very much to learn concerning the species’ behavior and ecology.

13·5 cm; male 10·5–13 g, one probable female 11·5 g. Male has crown and upper back grey, brown wash on back; rear crown and back with minute white or pale buff spots; rump and uppertail-coverts light reddish-brown, tail grey-brown with narrow white tip, edges of rectrices lined with small black-bordered buff spots; wings reddish-brown, wing-coverts and tertials with small terminal white or buff spots; face and side of neck pale grey, throat and breast whitish or very pale buff with minute dusky spots, lower breast and belly buff, small dusky spots on breast, flanks faintly barred dusky; iris whitish; upper mandible dusky, lower pale; tarsus brownish. Female is similar, but brown, not grey, above, and perhaps more buffy on underparts. Juvenile not described.

SE Brazil from SE Minas Gerais and W Espírito Santo S to N & NE Rio Grande do Sul (3 Bencke, G.A. (2010). New and significant bird records from Rio Grande do Sul, with comments on biogeography and conservation of the southern Brazilian avifauna. Iheringia, Sér. Zool. 100(4): 391–402. Close ), and adjacent NE Argentina (Misiones); probably also SE Paraguay.

Large stands of bamboo at edge of dense secondary forest, less often in vine tangles and other dense vegetation; at 600–1000 m in N, down to 300 m in S.

Probably sedentary.

Feeds on insects and larvae. Alone or in pairs. Average foraging height 2 m, but will climb as high as 7 m in dense vines; hops tirelessly through branches, fore part of body held low and tail cocked. Occasionally on the ground.

Song (very loud for bird’s size) 13–20 seconds long, a repetition of a loud, level or rising, pure (at high excitement churred) note at 0·9–1 kHz, 2·4–3 notes per second, “wood-wood-wood”, during first 2–3 seconds volume increasing and pitch slightly falling or rising; pauses between songs c. 16 seconds (less after playback).

Nothing known.

Not globally threatened. Currently considered Near-threatened. Restricted-range species: present in Atlantic forest lowlands EBA. Rare to locally uncommon; possibly overlooked owing to shyness and the fact that it sings only rarely. In Brazil, occurs in Serra do Mar, Alto do Ribeira, Intervales, and Carlos Botelho State Parks, and in Iguaçu National Park; in Argentina in Iguazú National Park. Lowland habitats in its range have for many decades been depleted through deforestation and conversion to agriculture; continued agricultural expansion, and urbanization, industrialization, human settlement and associated road-building, are current main threats.