The black-and-white monjita (Xolmis dominicanus) is a species of bird in the family Tyrannidae.It is found in Argentina, Brazil, Uruguay (where it can still be found at the Quebrada de los Cuervos), and possibly Paraguay. Its natural habitats are subtropical or tropical dry lowland grassland, subtropical or tropical seasonally wet or flooded lowland grassland, arable land, and pastureland.It is threatened by habitat loss.This species is sometimes separated in the monotypic genus Heteroxolmis.