Primates of Guayana Shield Forests

Abstract

The Guayana Shield represents a land mass of 1,800,000 km2 in northern South America (Kelloff & Funk 1995). Dating from the Precambrian, it has dominated the interior regions of the Guianas (Guyana, Suriname, and French Guiana), Venezuela, northern Brazil and southeastern Colombia (American Geographical Society 1978). Ten of the 16 platyrrhine genera (following the taxonomic arrangement of Schneider and Rosenberger, this volume) are known from forests either on or bordering the Shield. The most poorly represented subfamily is the Callitrichinae with only one of the five callitrichine genera present from this region. Only one species of tamarin, Saguinus midas, is found in the entire area. Both cebine genera (Cebus and Saimiri) are well-represented with interrupted distributions only in Venezuela. Of the three pitheciin genera (Pithecia, Cacajao,and Chiropotes), Pithecia has the broadest distribution and Cacajao has a very limited distribution. Aotus and Callicebus are found only in Bolivar and Amazonas states of southern Venezuela. Both species appear to be rare, but may also be under represented in surveys. Brachyteles and Lagothrix are absent from Guayana Shield forests, but both Ateles and Alouatta are broadly distributed. There is also a notable absence of endemic primate genera and species from these habitats suggesting that migration corridors into Shield forests from central or eastern Brazil have been open for thousands of years.