Bolivia, Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Guyana, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago, Venezuela.
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is unknown (2010).
White-flanked Antwren (Myrmotherula axillaris) [XC497198]
by Jacob Wijpkema from Bolpebra, Nicolas Suarez, Pando Department, Bolivia (song)
White-flanked Antwren (Myrmotherula axillaris) [XC262050]
by Olaf Jahn from Esmeraldas: Awacachi Biological Corridor, R\u00edo Bogot\u00e1 area, Ecuador (call, filght calls)
Subspecies
According to genetic studies, may be most closely related to Long-winged Antwren (Myrmotherula longipennis) and Grey Antwren (Myrmotherula menetriesii). Also, Rio de Janeiro Antwren (Myrmotherula fluminensis) thought by some to be possibly a variant of subspecies luctuosa of present species or, earlier, a hybrid between it and Unicolored Antwren (Myrmotherula unicolor). Often grouped with those four species and Slaty Antwren (Myrmotherula schisticolor), Rio Suno Antwren (Myrmotherula sunensis), Salvadori's Antwren (Myrmotherula minor), Ihering's Antwren (Myrmotherula iheringi), Plain-winged Antwren (Myrmotherula behni), Ashy Antwren (Myrmotherula grisea), Alagoas Antwren (Myrmotherula snowi) and Band-tailed Antwren (Myrmotherula urosticta) as the "grey antwren assemblage", although this grouping possibly not monophyletic. Substantial geographical differences in vocalizations strongly suggest that present species should be split into several distinct species, but further work required. Otherwise, morphological distinctions between subspecies heterozyga and fresnayana unclear. Distributions of subspecies given below are tentative, based primarily on previous published statements.
The following 6 subspecies are recognised:
albigula Lawrence, 1865 - Caribbean slope from south-eastern Honduras south to Colombia (except Santa Marta Mts), and Pacific slope from central Panama (Panamá, Darién) south to Ecuador.
melaena (Sclater, PL, 1857) - Santa Marta Mts and Colombia east of Andes, western Venezuela (Andean slopes east to Mérida and Barinas and, south of R Orinoco, east to R Caura), north-western Brazil (upper R Negro south to northern bank of R Amazon), eastern Ecuador and north-eastern Peru (Amazonas, San Martín, Loreto).
axillaris (Vieillot, 1817) - Eastern Venezuela (Apure, Monagas, Delta Amacuro, and south of R Orinoco east of R Caura), Trinidad, the Guianas, eastern Amazonian Brazil (from both banks of lower R Negro east to Amapá and, south of R Amazon, east of R Madeira to Maranhío and south to north-eastern Mato Grosso and Tocantins) and north-eastern Bolivia (north-eastern Santa Cruz).
heterozyga Zimmer, JT, 1932 - East-central Peru (Ucayali south to Madre de Dios) and south-western Amazonian Brazil (west of R Madeira).
fresnayana (d'Orbigny, 1835) - Extreme south-eastern Peru (Puno) and north-western Bolivia (west of R Mamoré, and along base of Andes east to western Santa Cruz).
luctuosa Pelzeln, 1868 - Coastal eastern Brazil (Paraíba south to Rio de Janeiro). Considered by some authors to be a distinct species, Silvery-flanked Antwren (Myrmotherula luctuosa).
BirdLife International Species Factsheet