South-eastern Bolivia and central Brazil (southern from Mato Grosso, southern Tocantins, Goiás, and western Minas Gerais), southern throughout Paraguay and Uruguay to north-eastern and central Argentina (south to Río Negro and north-eastern Chubut).
 
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is unknown (2010).
Screaming Cowbird (Molothrus rufoaxillaris) [XC49301]
by Rosendo Fraga from Monte Yucat, San Mart\u00edn, Cordoba, -32.36, -63.64, Argentina (song)
Screaming Cowbird (Molothrus rufoaxillaris) [XC507909]
by JAYRSON ARAUJO DE OLIVEIRA from Chapad\u00e3o do C\u00e9u, Chapad\u00e3o do C\u00e9u, Goi\u00e1s, Brazil (song)
Subspecies
Analyses of mitochondrial DNA indicate closest relationship with Giant Cowbird (Molothrus oryzivorus) and Bronzed Cowbird (Molothrus aeneus).