DistributionRead full entry
Range DescriptionWe are following here the taxonomy and proposed distributions of Silva Jr (2001). The taxonomic arrangement proposed by Groves (2001) was discussed by Rylands et al. (2005), especially in relation to the work of Torres de Assumpção (1983). It was not possible to delimit the ranges of the subspecies he recognized, but those of the species were mapped in Fragaszy et al. (2004).
The range of Cebus macocephalus described here includes those of the following taxa recognized by Groves (2001): C. apella fatuellus (Linnaeus, 1766) from Colombia, C. a. peruanus Thomas, 1901 from Peru; 1939, C. libidinosus juruanus Lönnberg, 1939 (in part) from the upper Rio Juruá. Cebus apella maranonis Von Pusch, 1941, recognized by Aquino and Encarnación (1994), is considered by Silva Jr. (2001) to be a junior synonym of C. macrocephalus, and by Groves (2001) to be a junior synonym of C. a . peruanus.
For Colombia, Defler (2004) described its range as follows: the entire Colombian Amazon, and all of the piedmont forest at least to 1,300 m above sea level, east of the Cordilleras, with the exception of some eastern areas such eastern Vichada and upper Cahuinari. It is also absent from much of the Colombian trapezium. C. macrocephalus (which he referred to as C. apella) is found also in upper valley of the Río Magdalena in Huila, up to 2,700 m above sea level (in the region of San Agustín) and the region of Tierradentro in Cacua to elevations of about 2,500 m (close to Inzá). Following Silva Jr. (2001), C. macrocephalus extends east to the Río Orinoco (C. apella is the form in the Venezuelan Amazon), occurring along the right bank of the Rio Negro to approximately São Gabriel Cachoeira where it is range is then delimited by a line approximately SSE across the Negro-Solimões interfluvium to the region of Coarí (on the Solimões) and then extending across the basin of the Rio Purus to the junction of the Ríos Madre Dios and Guaporé. From there its southern range is delimited by the Madre de Dios in Bolivia (C. apella occurs to the south of the Madre de Dios) west into Peru. Following Aquino and Encarnación (1994) its range then takes on all of the Peruvian Amazon north of the Rio Madre de Dios, but extending across the river to the south beyond the mouth of the Río Inambari (a southern tributary of the Madre de Dios). In Peru, C. macrocephalus (sensu Silva Jr, 2001) has been recorded at altitudes up to 1,800 m above sea level (Aquino and Encarnación 1994).