Spot-backed Antwren Herpsilochmus dorsimaculatus

Small canopy antwren with a long, graduated tail. Males are largely gray with a black crown and a bold white eyebrow; the black spots on the back can be difficult to see. Females have a buff forehead and breast sides, with the black crown spotted white. Inhabits humid lowland forest and seasonally flooded forest in some regions. Almost invariably seen accompanying canopy mixed-species flocks. The song is a somewhat deep trill that slightly ascends and then descends: “wiwiwurrrrr.”