The coppery titi monkey, Callicebus cupreus
Callicebus cupreus one of the first species of titi monkeys to be described. Spix (1823) had collected the species in forest along the Río Solimoes in Brazil, near the border with Peru. He described it as being “grey-brownish on the upper parts, and coppery on the under parts and the legs. The head covered is with short red hairs; the middle of the face is almost naked. The face is contoured from the temples to the lower cheeks with coppery coloured hairs, directed forwards. The lips and chin are covered with small black rigid hairs. The ears are naked on the backside, covered with some red hairs on the other side. Generally all hairs are directed backwards; those of the back, upper arm and thighs relatively long, black and on the same time mixed with red. The tail which is grey-reddish, becomes towards the tip paler and white. The eyes are brown”.
In 1848 Geoffroy Saint-Hilaire and Deville described Callithrix discolor. After a study of the type specimens and a thorough reading of the description, I can only conclude that discolor is a junior synonym of Callicebus cupreus (the type specimens do NOT have a white frontal blaze, as is generally believed). Other junior synonyms are probably the very dark Callicebus usto-fuscus (Elliot, 1907) and Callicebus egeria (Thomas, 1908), although the latter has a striking light-greyish occiput.
Its distribution range is on both sides of the Río Javari, in Peru and Brazil.