erythrocebus is a genus of old world monkey. both species in this genus are found in africa, and are known as patas monkeys. while formerly considered a monotypic genus, a recent review has argued that some of the northeast african populations are a distinct species, "e. poliophaeus", proposing in addition that the subspecies "e. p. pyrrhonotus" be elevated to full specific status, along with the formerly recognised subspecies "e. p. baumstarki" for the population in tanzania.