This warbling finch ranges from southern Brazil to southern Argentina and the Paraná basin of Paraguay. Its plumage and habitat differ from those of a close relative, P. whitii.
Males have tawny-rufous throats, breasts and flanks, with brownish-gray, slate-tinged upperparts. Females have an orange tinge below and more olive upperparts.
The paper records the species in open wetland shrub and reed patches as well as grassland. It also compares responses to vocalizations of P. nigrorufa and related P. whitii.
An extinction-risk assessment has not been added yet.