Eastern Brazil in interior eastern Bahia and north-eastern Minas Gerais.
 
Population
Estimated population is unknown (2010) and decreasing.
Status NT
Habitat destruction and degradation through clearing for cattle pasture, coffee plantations, exploitation of trees for firewood and fenceposts, is the main threat.
For more information see BirdLife International Species Factsheet.
Habits
Forages singly or in pairs. Sometimes with flocks.
Voice
Male song is a musical series of 7-12 (2 per second) metallic 'píeep' notes. Female gives a shorter, softer version.
Narrow-billed Antwren (Formicivora iheringi) [XC707211]
by Mateus Gon\u00e7alves Santos from Mata do Lobo, Brazil (song)
Narrow-billed Antwren (Formicivora iheringi) [XC340427]
by Ciro Albano from Po\u00e7\u00f5es, Bahia, Brazil (song)
Subspecies
Relationships unclear. Recent extensive morphological and vocal study indicated that it is not closely related to others of genus, and that it should perhaps, for the time being, be placed in a separate monotypic genus. Further research is required.
No subspecies.
Similar Species
Subspecies luctuosa of White-flanked Antwren (Myrmotherula axillaris) is shorter tailed and female has less rufescent uppertail-coverts and less uniform ochre underparts. Apparently not sympatric.
References
See References.