A taxonomic revision of the Musician Wren, <i>Cyphorhinus</i> <i>arada</i> (Aves, Troglodytidae), reveals the existence of six valid species endemic to the Amazon basin.

Cyphorhinus arada, an Amazonian endemic, shows considerable geographic variation in plumage that has led to the recognition of eight subspecies. These include C. a. arada, C. a. salvini, C. a. modulator, C. a. transfluvialis, C. a. interpositus, C. a. griseolateralis, C. a. urbanoi and C. a. faroensis. However, a thorough taxonomic revision of the Cyphorhinus arada complex has never been undertaken, so we revise the taxonomy based on morphological and vocal characters. We analyzed a total of 515 museum specimens and 146 voice recordings representing and encompassing the distributions of all named taxa, including those currently considered not valid. Vocal analyses showed major variation within the complex, from which several trends could be identified between populations. We concluded that six species (C. arada, C. transfluvialis, C. modulator, C. salvini, C. interpositus and C. griseolateralis) should be recognized under the Phylogenetic Species Concept based on the diagnosis of stable plumage and vocal patterns of each.