The severely threatened Rio Branco Antbird (Cercomacra) is endemic to the subtropical or tropical moist lowland forests and subtropical or tropical moist shrublands of Roraima in Brazil and parts of southwest Guyana along the Ireng River. These birds prefer the dense forests with vines and river islands, and are usually observed in pairs. Its plumage (black in males) suggests that it forms a species group with other antbirds found in the same habitat.