Plain-breasted piculet endemic to South America on the eastern side of the Andes where it lives in the western part of the Amazon basin. The species is present in southern Colombia, eastern Ecuador, Peru and western Brazil at altitudes of up to . It is found in open parts of humid lowland forests, flooded forests, riverside corridors, swamps, thickets and groves, and logged areas with secondary growth and wooded pastures. It often occurs in areas of young "Cecropia" and "Mimosa" trees. The plain-breasted piculet is usually seen by itself or in pairs, but it will occasionally joins small flocks of birds of
Piculet of pronounced morphological similarities, but the two "Picumnus" lineages, despite having diverged long ago, are virtually alike except for head coloration (Fuchs "et al.", 2006). The Antillean piculet ("Nesoctites micromegas") has proven to be a very distinct species evolutionarily between piculets and woodpeckers (Benz "et al.", 2006) and thus is nowadays placed in a subfamily of its own. The arrangement of species in the genera follows del Hoyo "et al." (2002). Genus "Picumnus" Genus "Verreauxia" (sometimes included in "Sasia") Genus "Sasia" Piculet The piculets are a distinctive subfamily, Picumninae, of small woodpeckers which occur mainly in tropical South America, with