Rondonia Warbling-Antbird Hypocnemis ochrogyna Scientific name definitions

Rondonia Warbling-Antbird has a comparatively small distribution in southwest Amazonia, being principally found in Brazil, where its range is centered on the state of Rondônia, but with a relatively minor extension of its range into northeast Bolivia. From Peruvian Warbling-Antbird (Hypocnemis peruviana), its range is separated by the Rio Madeira, while from Spix’s Warbling-Antbird (Hypocnemis striata), which occurs to the north and east of the present species, it is separated by the Rio Roosevelt. Possibly, the range Rondonia Warbling-Antbird also might come close to that of Yellow-breasted Warbling-Antbird (Hypocnemis subflava) in northern Bolivia, but this has yet to be definitely established. In the event that they do, then these two will be easily separated on plumage features alone.

11–12 cm; 11–15 g. Typical member of the H. cantator species complex, whose range abuts those of the recently described H. rondoni (to the N, with which it is potentially parapatric), as well as H. striata (to the NE), H. subflava (to the W) and H. peruviana (to the NW), from all of which it is generally most easily distinguished using vocal characters. Compared to H. striata, male of the present species differs in its grey rather than black mantle  and less heavily streaked breast  , while female  has pale ochraceous-brown versus strongly streaked black-and-rufescent mantle and back; versus H. peruviana, present species has paler rufous flanks  , and in female lightly marked, pale ochraceous-brown mantle and back rather than black-and-buff-streaked; however, H. rondoni is potentially extremely similar, certainly differing only in the stronger rufous edges to the bases of rectrices. Finally, H. subflava differs from present species (and all others in the complex) in having unmarked pale yellow throat to belly, very weak rufous on flanks and a pale olive-grey (rather than rufous-toned) rump.

• Rondonia x Spix's Warbling-Antbird (hybrid) Hypocnemis ochrogyna x striata

E Bolivia (E Beni, N Santa Cruz) and SC Amazonian Brazil (Rondônia, W Mato Grosso).

For general characteristics of male and female loudsongs, plus calls, see relevant section of account for H. cantator. Male loudsong is unusual in being relatively even-paced, unlike all other members of the species complex in which they either decelerate or accelerate, with peaks of the initial 4–6 notes increasing gradually and the initial note substantially longer than the clear notes that follow. Female loudsong starts with a long note and ends in an abrupt note (leaving aside terminal raspy notes), with peak frequencies of the first three notes ascending (unlike all former conspecifics). The common call is most like that of H. peruviana (which see), in becoming steadily downslurred with each note, but unlike the latter species each note also becomes shorter and usually more raspy, although on current knowledge the two species are not diagnosably different in this character. Also gives abrupt “chit” calls like all other members of the H. cantator species complex.

VULNERABLE. Fairly common to common throughout most of its range, but global population unknown. Has lost an estimated 60% of its habitat in Brazil over the past 40 years, while in the state of Rondônia forest loss has been estimated at 22–37% over the last 15 years BirdLife International (2017) Species factsheet: Hypocnemis ochrogyna. Downloaded from http://www.birdlife.org on 31/12/2017. . Since Brazil accounts for more than half of the species’ range, it is suspected to have undergone a decline of >30% over 10 years or three generations BirdLife International (2017) Species factsheet: Hypocnemis ochrogyna. Downloaded from http://www.birdlife.org on 31/12/2017. . For these reasons it was assessed as Vulnerable in 2017. Known from several protected areas, including Noel Kempff Mercado National Park (IUCN Cat. II; 15,234 km²) and Caparú Biological Station, in Bolivia, and Serra da Cutia National Park (IUCN Cat. II; 2835 km²) and Traçadal Biological Reserve, in Brazil. Considered Vulnerable at the national level in Brazil (1 MMA (2014). Lista Nacional Oficial de Espécies da Fauna Ameaçadas de Extinção. Portaria No 444, de 17 de dezembro de 2014. Diário Oficial da União - Seção 1. Nº 245, quinta-feira, 18 de dezembro de 2014. Close )(MMA 2014).