We report a new record of Eurhopalothrix bruchi(Santschi, 1922) from a mountain system in central-eastern Argentina. This is the southernmost record for the species, and the first reported from grassland habitats. One worker was collected in a pitfall trap during a survey of the myrmecofauna in Ernesto Tornquist Provincial Park, Buenos Aires, Argentina (38°03ʹ41ʺ S, 061°59ʹ18ʺ W; 700 m above sea level), in the summer of 2012–2013. We compile previous records in the Neotropics of this species and update the current geographical distribution.