Animal Facts

Slow Loris

Scientific Name: Nycticebus coucang

Fast Fact:

Lorises are classified as prosimians, meaning “before the monkeys.” They exhibit more primitive characteristics than advanced primates like monkeys and apes.

Slow Loris

The slow loris is a small, solitary, nocturnal primate living in the forests of Southeast Asia. With its soft, gray to light-brown fur and its ability to stay motionless for hours, it blends into its habitat so well that it is difficult to see unless one uses a powerful flashlight. The first visible sign will be the bright shining glow of the loris’s eyes, reflected in the torchlight because of a layer in the retina called the tapetum, which gives forth “eye-shine” when illuminated by the moon or by artificial light. Many nocturnal animals, like cats, share this tapetum.

STATUS: The slow loris is listed as Vulnerable by the International Union for Conservation of Nature (IUCN). Their survival depends on the fast-disappearing tropical forests. A survivor from the beginnings of primate evolution 50 million years ago, the loris is a seldom seen but successful little animal of considerable fascination and beauty.

HABITAT: The slow loris has a wide range of habitats in South China, Northern India, Burma, Thailand, Vietnam, Malaysia, Cambodia, Laos, the Philippines, and Indonesia. Its relatives, the slender loris (found only in southern India) and the pygmy loris (found only in Southeast Asia) have smaller ranges.

DIET: The slow loris’s wide range may be partly due to its adaptability. Its omnivorous diet includes about 50% fruit and 30% animal protein, including birds’ eggs and insects, and about 10% gum, the high-glucose sap exuded from trees. They also eat fresh green shoots from tropical plants, and sometimes, plants from human crops like cocoa. They can eat with both grasping hands while hanging upside-down by their feet.

PHYSICAL CHARACTERISTICS: Being small and inconspicuous helps lorises hide from predators like snakes and carnivorous mammals like jungle cats. They can hang tightly to a branch for hours without their muscles becoming numb because they have a special network of blood vessels providing oxygen to their extremities.

Gestation is about six months. Babies hang on to mothers for about seven weeks, and nurse for six months. Females become sexually mature between 17 and 21 months, and give birth to a single young. Lorises grow to about 15 inches long, with one-inch tails, and can weigh three pounds. They can live to 20 years.

Not As “Slow” As You Might Think...

Despite their low metabolism, when alarmed, lorises can move quickly to safety through the tangles of branches. Sometimes described as a “stealth hunter,” the loris can lunge at prey. Adult lorises sleep alone, curled up in a ball with the head tucked between the legs. They mark territories with urine or with secretions from scent glands on their arms. Though usually quiet, lorises can make low-pitched calls. Females ready to mate make high-pitched whistles. When startled or frightened, lorises buzz or hiss. Babies are thought to call to their mothers with ultrasound.

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