Varzea piculet Snethlage who collected birds in Brazil for two decades. The specific name refers to ""várzea"", the Brazilian name for the seasonally flooded forested area close to the Amazon River. There are no subspecies. This bird occasionally hybridises with the white-barred piculet "(Picumnus cirratus)". The varzea piculet is a small species, some in length. The male differs from the female in having variable amounts of red on the fore and mid-crown; this red patch is the result of the crown feathers having broad red tips, and the rest of the crown in males and the whole crown in females is black
White-barred piculet northeastern Brazil; "P. c. thamnophiloides" found in southeastern Bolivia and northeastern Argentina; "P. c. tucumanus" found in northwestern Argentina; the Pilcomayo piculet, "P. c. pilcomayensis" found in southeastern Bolivia, Paraguay and northeastern Argentina; and the nominate subspecies "P. c. cirratus" found in southeastern Brazil, southern Mato Grosso and eastern Paraguay. The taxonomy of this species is difficult; the races "pilcomayensis", "thamnophiloides" and "tucumanus" intergrade in northern Argentina and are sometimes considered a separate species, and "pilcomayensis" intergrades with "cirratus" in eastern Paraguay. The northern subspecies, "confusus" and "macconnelli" may also be a distinct species. The white-barred piculet also hybridizes widely