Atualização do Conhecimento Sobre o Sauim-De-Cara-Suja, Saguinus weddelli (Primates, Callitrichinae), no Estado De Rondônia

This study consists of an update on the knowledge of the geographical distribution and population data of the saddle-back tamarin (Saguinus weddelli) in the area lying east of the Madeira River in Rondônia. A literature review were conducted as well as a series of expeditions in the municipalities of Cacoal, Machadinho D'Oeste, Nova Brasilândia D'Oeste, Chupinguaia, São Francisco do Guaporé and Costa Marques. The results indicated the existence of 39 sites where S. weddelli was recorded in the study area, 31 obtained from the literature and eight resulting from fieldwork. One of the new records is located beyond the known geographic range of the species, representing an extension of such a range. Although this taxon is not considered endangered, its status in the study area deserves attention, since high rates of deforestation in this region have been recorded during the past 40 years.