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
Black-dotted piculet Sucre, a few have finely barred chests. Rare individuals with scaly throats and pale buffy (rather than yellow) underparts resemble the scaled piculet, which can be distinguished by its scaly lower underparts. The crown is black with narrow scarlet streaks on the forepart and conspicuous white dots on the rear part, or throughout in some females. The upperparts are light olive-brown, slightly yellowish, with dusky spots on the shoulders and back. The song is "2 to several extremely high, thin notes, each slightly lower than the preceding, "tseeet, tseeet, tsee," etc." Possibly it is also used as a contact call.