New Species Of Night Monkey Found In Peru

23rd November 2012

New species of mammals are not easy to come across nowadays, so the team was lucky enough to see this fox, but within the 29,500 ha sanctuary of misty cloud forests and alpine pastures, the researchers found an incredible eight new species of mammals, plus three amphibians.
Pictured above is the new species of night monkey, which the team have yet to name. Otherwise known as owl monkeys, because they’re the only known truly nocturnal monkeys, night monkeys from southern Central America and northern South America are still quite a mystery. They’re rare and very few have been observed in the wild, so we’re not sure how long they live outside of captivity, or even what their average weight and length is. The Save the Primates website quotes a Peruvian hunter as having told a reporter in 2007 that,  “The monkeys are elusive… in order to capture them, we have to take down 30 metres of forest around the tree where they are located.”
What we do know about the members of the Aotus genus is that they have a very similar reaction to the human malaria virus that we do, making them popular research subjects. They also have unusual eyes, their colour vision is quite poor, probably due to the fact that it’s not particularly useful in the dark anyway, but have superior spatial resolution at low-light levels, which helps them to spot insects moving around in the dark.
Like the wide-eyed tarsier, night monkeys also lack a tapetum lucidum. This is the tissue layer in the eye that causes it to reflect light, producing what’s known as ‘eye shine’ in of many other nocturnal animals such as opossums, aye ayes, cats and reptiles. In a 1983 paper in the American Journal of Primatology describing two new species of night monkey, Philip Hershkovitz from the Field Museum of Natural History in Chicago writes, “In addition to my years of experience night hunting Aotus and other nocturnal mammals, I have tested with flashlight the eyes of well over 100 captive night monkeys, more than 60 of them in the outdoor compounds of the Proyecto Primates in Iquitos, Peru. The eyes of Aotus did not shine at any time or place like those of nocturnal animals with tapetum lucidum.” Hershkovtiz also quotes , a pair of researchers called Muckenhirn and Montgomery, who radiotracked a night monkey in the 1970s, reporting that, “there were long periods during which we could not see or hear it. It moved quietly through the trees, did not vocalise, and usually did not drop rinds as it fed.” A night monkey is no easy find.