The Proboscis Monkey (Nasalis larvatus) is very odd looking. The nose is very long, close to three inches. The male's nose is generally bigger than the females. It has been suggested that the males with the biggest noses are more attractive to the lady monkeys. This monkey's call sounds like "honk or kee-honk." This monkey is found in mangrove swamps and riverside forests in Borneo and is about 2 to 3 feet tall. The males are much larger than the females. Coloration is reddish. This is a tree-dweller, likes to live near water and is an excellent swimmer.
Breeding can take place any time of year and there is usually just one offspring born after about 166 days gestation. The Proboscis Monkey is a vegetarian and eats leaves and fruit. It travels in small groups.