Kleinhakentyrann Agriornis murinus

Small (and small-billed) shrike-tyrant of open country in the southern cone, more reminiscent of a monjita than a shrike-tyrant. Note small bill, lacking terminal hook. Breeds in northern Patagonia and the southern Monte desert, as well as the Sierra de Comenchingones in central Argentina. Disperses northward and upslope into W Paraguay and SE Bolivia during the austral winter. Prefers exposed perches in low vegetation, wires, and shrubs.