Black-faced grassquit

Adult black-faced grassquits are 10.2 cm long and weigh 10.5 g. They have a short conical black bill with an obvious curve to the culmen. The male is olive green above, paler grey-olive below, and has a black head and breast. Female and immature birds have dull olive-grey upperparts and head, and paler grey underparts becoming whiter on the belly.