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) [XC236167]
by Odirlei Vieira da Fonseca from Parna Capara\u00f3, Alto Capara\u00f3, Minas Gerais, Brazil (song)
Mouse-colored Tapaculo (Scytalopus) [XC727634]
by Carlos Henrique Luz Nunes de Almeida from Itatiaia National Park, Tr\u00eas Picos trail, Itatiaia, Rio de Janeiro, 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.