Relatively wide ranging species found in the Pando Department in northern Bolivia (Anderson 1997), north of the Río Madre de dios in the Beni Department (Rowe and Martinez 2003; R. Wallace, pers. obs.), extending into south-eastern Peru and north into Brazil (Hershkovitz 1988, 1990) into the state of Rondônia (between the Mamoré, Madeira and Jiparaná rivers); possibly limited to the south in Brazil by the Serra dos Pacaás (Ferrari et al. 2000). Further surveys are required in Bolivia to establish the number and identity of Callicebus species in this region (R. Wallace, pers. obs.).