Douroucouli/Night Monkey - Red-necked Aotus species

The Douroucoulis, also called Night Monkeys and Owl Monkeys, as the name indicates, are active mainly at night. They are small monkeys native to jungles/forests of Central and South America.

Bolivian Douroucouli
Bolivian Douroucouli
The several species of Night Monkey are divided into two groups, the red-necked, on this page, with ginger chest fur, and the grey-necked (link below). Some are active in the day if safety allows.
Bolivian Douroucouli
Night Monkey Azara's
Owl Monkey Bolivian
Above is the Bolivian subspecies of Azara's Night Monkey, Aotus azarae boliviensis, also called the Southern. Like other Night Monkeys, it lives in mainly monogamous pairs with the father taking on most parental care of offspring. They are important dispersers of seeds and clearers of branches.
  
Maroon line
Black-headed Night Monkey
Black-headed Night Monkey
Above is the Black-headed Night Monkey, Aotus nigriceps, native to Bolivia, Peru, Colombia and Brazil. Tame and active in daylight in a park in Peru.
  
Maroon line