The yellow-handed titi monkey, Callicebus lucifer
Oldfield Thomas described in 1927 a new titi monkey, Callicebus lucifer, based on a specimen from Loreto, Peru. He indicates that the new species is “like C. lugens (syn. Amictus, Geoff.), but the tail chestnut-rufous instead of black. Belly black, not red as in C. torquatus”.
Its distribution is restricted to the Amazon Basin of South-East Colombia, North-Eastern Ecuador, Northern Peru and North-Western Brazil.