Cercocebus fuliginosus

from The Collaborative International Dictionary of English v.0.48
Mangabey \Man"ga*bey\, n. [So called by Buffon from Mangaby, in
   Madagascar, where he erroneously supposed them be native.]
   (Zool.)
   Any one of several African monkeys of the genus {Cercocebus},
   as the sooty mangabey ({Cercocebus fuliginosus}), which is
   sooty black. [Also written {mangaby}.]
   [1913 Webster]
    

[email protected]