Murray Cooper / Monk Saki (Pithecia monachus) in tree, Ecuador

Murray Cooper / Monk Saki (Pithecia monachus) in tree, Ecuador

Murray Cooper / Monk Saki (Pithecia monachus) calling, Ecuador

Murray Cooper / Monk Saki (Pithecia monachus) in tree, Ecuador

Juan Manuel Borrero / White-faced Saki (Pithecia pithecia) head portrait lying against tree trunk, captive, Isla de los Monos (Monkey island). Amazon river. Loreto. Peru

Juan Manuel Borrero / Monk saki monkey (Pithecia monachus) sitting on tree branch, captive, Isla de los Monos (Monkey island) Amazon river. Loreto. Peru

Rod Williams / White-faced Saki Monkey (Pithecia pithecia) juvenile feeding on vegetation, from northeastern South America, captive.

JIM CLARE / White faced saki monkey {Pithecia pithecia} male, Captive, from Amazonia, South America

Edwin Giesbers / White-faced Saki Monkey (Pithecia pithecia) head portrait of male. Captive, Netherlands.

Edwin Giesbers / White-faced Saki Monkey (Pithecia pithecia) female nursing young. Captive, Netherlands.

Barry Mansell / White faced saki monkey (Pithecia pithecia) on branch, captive, found North and Central South America

Barry Mansell / White faced saki monkey (Pithecia pithecia) on branch, captive, found North and Central South America, Columbia to Peru

Mark Bowler / Geoffroy's monk saki (Pithecia monachus), Rio Yanayacu, Pacaya-Samiria National Park, Peruvian Amazon, Peru

Mark Bowler / Equatorial saki monkey (Pithecia aequatorialis) sitting on branch, Peruvian Amazon, Peru

Thomas Marent / Monk Saki (Pithecia monachus), Pacaya Samiria National Park, Peru

Thomas Marent / Monk Saki (Pithecia monachus), Pacaya Samiria National Park, Peru

Thomas Marent / Monk Saki (Pithecia monachus), Pacaya Samiria National Park, Peru

Thomas Marent / Monk Saki (Pithecia monachus) eating, Pacaya Samiria National Park, Peru

Thomas Marent / Monk Saki (Pithecia monachus), Pacaya Samiria National Park, Peru

Thomas Marent / Monk Saki (Pithecia monachus) portrait, Pacaya Samiria National Park, Peru

Nick Gordon / Monk saki monkey (Pithecia irrorata) eating seeds from pod, Amazonia, Brazil

Nick Gordon / Monk saki monkey (Pithecia irrorata) eating from seed pod, Amazonia Brazil

Nick Gordon / Spot faced saki (Pithecia albicans) Amazonia, Brazil

Ingo Arndt / Equatorial Saki (Pithecia aequatorialis) sucking its thumb, Amazon ecosystem, Peru

Ingo Arndt / White-faced Saki (Pithecia pithecia) portrait, South America

Luiz Claudio Marigo / Gray's bald faced saki (Pithecia irrorata), Amazonas, Brazil

Nick Gordon / Spot faced Saki monkeys {Pithecia albicans} Amazon, Brazil, South America

JIM CLARE / White faced saki pair {Pithecia pithecia} male on left, female on right feeding, Amazonia, South America

Nick Gordon / Spot faced saki {Pithecia albinasus} Amazonia, Brazil

Rod Williams / White faced saki {Pithecia pithecia} male, captive, from Amazon rainforest

JIM CLARE / White faced saki monkey {Pithecia pithecia} female, from Amazon rainforest

JIM CLARE / White faced saki monkey {Pithecia pithecia} female, from Amazon rainforest

Dave Watts / White faced saki monkey {Pithecia pithecia} Sputh America

Rod Williams / White faced saki monkey {Pithecia pithecia} with young, captive, from South America

Tony Heald / White faced saki had portrait {Pithecia pithecia}, male, Shaldon Zoo, UK. Captive. Occurs South America

Luiz Claudio Marigo / Gray's bald faced saki (Pithecia irrorata), Amazonas, Brazil

Luiz Claudio Marigo / Gray's bald faced saki (Pithecia irrorata), Amazonas, Brazil

Dave Watts / White-faced Saki monkey (Pithicia pithicia) Captive

Dave Watts / White-faced Saki monkey(Pithicia pithicia) mother with young male on back, Captive

Dave Watts / White-faced Saki mnonkey (Pithicia pithicia) Captive

Luiz Claudio Marigo / Sot faced / buffy saki monkey {Pithecia albicans} Amazonas, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia) portrait, Amazon ecosystem, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia) portrait, Amazon ecosystem, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia) clinging to tree trunk, Amazon ecosystem, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia) pair, Amazon ecosystem, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia), Amazon forest, Brazil

Claus Meyer / White-faced Saki (Pithecia pithecia) male portrait, Amazon forest, Brazil

Shin Yoshino / White-faced Saki (Pithecia pithecia) portrait, native to South America

Rod Williams / White faced saki monkey {Pithecia pithecia} South America, captive

Anup Shah / White faced saki monkey male {Pithecia pithecia}

Anup Shah / White faced saki monkey female {Pithecia pithecia}

Pete Oxford / Equatorial Saki (Pithecia aequatorialis) with radio collar, Tiputini Biodiversity Station, Amazon Rainforest, Ecuador

Thomas Marent / Monk Saki (Pithecia monachus), Pacaya Samiria National Park, Peru

Rod Williams / White-faced / Guianan Sakis (Pithecia pithecia) baby on adult's shoulders. Occurs Amazon Basin, E of Rios Negro and Orinoco, May 2OO8. Captive.

Luiz Claudio Marigo / Gray's bald faced saki (Pithecia irrorata), Amazonas, Brazil

Pete Oxford / White faced saki male {Pithecia pithecia} C S America