Eastern and south-eastern Brazil in interior southern Bahía, western Espírito Santo and southern Minas Gerais south to Rio Grande do Sul, and north-eastern Argentina (Misiones). Sight records from south-eastern Paraguay (Caazapá) require confirmation.
 
Population
Estimated population is unknown (2010).
Mouse-colored Tapaculo (Scytalopus speluncae) [XC671155]
by Brian Cox from Pico da Caled\u00f4nia, Nova Friburgo, RJ, Brazil (song)
Mouse-colored Tapaculo (Scytalopus) [XC18780]
by Robson Silva e Silva from Serra do Mar National Park - Santa Virginia - Sao Paulo State, Brazil (song)
Subspecies
No subspecies.
Closely related to Marsh Tapaculo (Scytalopus iraiensis). Some geographical variation in voice suggests that present species may involve more than a single taxon. Birds from north-eastern Argentina (Misiones) have longest bill and shortest wing, but no other differences sufficient to warrant subspecific separation.