Photo by Felipe Lopez Feb 2006 Mantled Howler Monkey The Mantled Howler (Alouatta palliata) is a species of howler monkey, a type of New World monkey, found in Central and South America. Howler monkeys are among the largest of the New World monkeys, ranging in size from 56-92cm, excluding their tail which can be as long again. They have a lifespan of 15 to 20 years. (From: Wikipedia, Apr. 2006). See Lodge information and prices.