Notes on Lagothrix flavicauda (Primates: Atelidae): oldest known specimen and the importance of the revisions of museum specimens

ABSTRACT The yellow-tailed woolly monkey, Lagothrix flavicauda (Humboldt, 1812), is a large atelid endemic to the cloud forests of Peru. The identity of this species was uncertain for at least 150 years, since its original description in 1812 without a voucher specimen. Additionally, the absence of expeditions to the remote Peruvian cloud forests made it impossible to collect material that would help to confirm the true identity of L. flavicauda during the 19th and first half of the 20th century. Until now, the specimens of L. flavicauda collected by H. Watkins, in 1925, in La Lejía (Amazonas...