Extreme southern and south-eastern Colombia (base of Andes in Caquetá, and Leticia area in south-eastern Amazonas), eastern Ecuador and north-eastern Peru (north of R Marañón and R Amazon).
 
Population
Estimated population is unknown (2010).
Dugand's Antwren (Herpsilochmus dugandi) [XC224138]
by John V. Moore from La Selva lodge, Napo, Ecuador (song)
Dugand's Antwren (Herpsilochmus dugandi) [XC484498]
by Jerome Fischer from Parque Nacional Yasun\u00ed, Orellana, Ecuador (call)
Subspecies
Herpsilochmus sticturus (Sibley and Monroe 1990, 1993) has been split into Spot-tailed Antwren (Herpsilochmus sticturus) and Dugand's Antwren (Herpsilochmus dugandi) following SACC (2005).
Forms a superspecies with Spot-tailed Antwren (Herpsilochmus sticturus) and formerly considered conspecific, but separated on basis of differences in female plumage and in calls.