Gray finch-like bird known from only a few sites in the Andes of northern Peru, including steep slopes above the Marañon Valley. Adult has bright yellow bill and legs, black mask, and white outer tail feathers that are hard to see when perched. Young birds have less black on the face and duller bill and legs. Inhabits arid regions with dense, scrubby forest. Forages mainly on the ground, but perches up higher to sing. Typical song is a rising, tremulous whistle.