Attractive sparrow found along the western edge of the Andes in northwestern Argentina, barely reaching over the border into Bolivia. Note the chestnut head stripes, dark smudge between eye and bill, and black and white mustache. Similar to Chaco Sparrow, with which it was formerly lumped as Stripe-capped Sparrow, but is larger with more extensive black on the face, rustier wings, and a different voice. Inhabits open, grassy habitats with scattered trees and low scrub. Song is a slow series of wheezy chirps.