We provide the first documented case of the extinction in the twentieth cen
tury of a widely recognized primate taxon. During surveys in Ghana and Cote
d'Ivoire in 1993-1999, we were unable to find any surviving populations of
Miss Waldron's red colobus monkey (Procolobus badius waldroni) a primate t
axon endemic to the forests of this part of West Africa We conclude that th
is monkey, which at least one authority considers worthy of species status,
is probably extinct. Hunting by humans appears to be the ultimate cause of
the extinction. Until our surveys began, little attention had been paid to
the plight of this red colobus monkey, despite its listing as endangered b
y the World Conservation Union. The extinction of other large animals in th
e Upper Guinea rainforest region is likely to follow soon unless more atten
tion is paid to the full range of endangered forms and more resources are d
evoted to their rigorous protection.