Lee Richardson Zoo

Pygmy Slow Loris

Pygmy slow lorisAKA Lesser Slow Loris

Order: Primates
Family: Lorisidae - Lorises, bush babies, and pottos
Scientific Name: Nycticebus pygmaeus
Description: The slow loris gets its name from the Dutch word “loris” which means “clown” and its slow, sloth-like movements. This small-bodied primate is only about 10” long and has a vestigial tail. Weighing approximately 11 oz., they have dense, short, wooly brown/grey fur and occasionally have a faint midline dorsal stripe. The head is round with a small pointed snout and large, moist, forward facing eyes while the ears are almost completely hidden by the fur. The body is rounded and stocky with short limbs, and flat, bare palms. Like all primates, they have opposable thumbs for gripping and nails on all of their digits. The nail on the second digit of the foot is elongated and rolled up to form a grooming claw. Aside from their long, sharp canines, they also have closely spaced incisors on the lower jaw that form a “tooth comb” which is helpful for removing insects, burrs, and snags from their pelts.

Home Range: East of the Mekong River in southern Yunnan, Laos, Viet Nam and eastern Cambodia. A limited range that overlaps extensively with that of the slow loris (N. coucang).


Habitat Type: Thick foliage tropical rainforests or bamboo groves.


Reproductive Habits: Gestation lasts approximately 192 days, after which the loris will give birth to 1-2 babies. They are able to reproduce every 12 – 18 months. Infants cling to their mothers’ bellies when first born, but the mothers will “park” their infants on a branch whenever they forage for food. Youngsters are soon capable of moving around short distances on branches after being parked and are weaned at about 133 days. Females reach sexual maturity around 9 months of age with the males reaching sexual maturity at around 18 to 20 months of age.


Diet in Wild: Fruit, arthropods, and gum (sap).


Diet in Zoo: Grapes, mealworms, mixed greens, mixed veggies/fruit, insectivore diet, browse biscuits, hard cooked egg.


General Info: All lorises have extremely strong fingers and toes, capable of maintaining a firm grip while remaining completely immobile for long periods of time. This is due to a specialized network of blood vessels in the limbs that prevent the muscles from becoming fatigued. The pygmy slow loris is arboreal and nocturnal, sleeping by day rolled up in a ball with their head between their legs clinging to branches in dense foliage. Due to a slow metabolism that makes maintaining a stable body temperature difficult, the pygmy slow loris depends on their thick fur to help keep them warm. They will often forage alone at night and are opportunistic feeders, consuming a wide variety of plant and animal material. They have even been observed gouging tree branches with their toothcomb to stimulate a flow of edible gum/sap. However, the pygmy slow loris does not eat leaves but will occasionally lick them for moisture. They are expert in catching insects, especially those with a strong odor, which they can find with their keen sense of smell. It is not uncommon to see them hanging upside-down from branches by their feet so that both of their hands can be free to help them eat. This species is more active at night and moves more quickly than some of the other lorises. They remain almost constantly in motion during darkness, pausing only briefly to feed.

If threatened, the pygmy slow loris can emit a strong odor in an attempt to deter a predator. If the predator persists, the pygmy slow loris can produce a secretion that is toxic when mixed with saliva and would then proceed to attempt to bite the predator. This secretion is also toxic to humans. As a last resort, the pygmy slow loris will drop to the ground and flee.


Status: Very little is known of their population status but they are considered the most endangered of all the non-lemur prosimians. Their restricted habitat has been subject to severe environmental disruption through military activity. Pygmy slow lorises are also taken from the wild in order to be sold as pets and for use in traditional medicine. They can frequently be found for sale at markets in Vietnam.

 They are listed on IUCN Red List as Vulnerable, CITES App. l., SSP; no studbook.


Grzimek’s Animal Life Encyclopedia. Second Edition. Vol. 14. Dr. H. C. Bernhard Grzimek. VanNostrand Reinhold Co., New York, N. Y. p 19.


Walkers Mammals of the World. Sixth Edition. Vol. l. R. Nowak. The Johns Hopkins University Press. Baltimore and London. 1999. Pp 497- 498.


Walkers Primates of the World. R. Nowalk. The Johns Hopkins University Press, Baltimore and London. 1999. Pp.57-58.


Pygmy Slow Loris. Duke University. 8 April 2010.

Nycticebus pygmaeus, lesser slow loris distribution. Map. 8 April 2010.


Husbandry Manual for Asian Lorisines. 9 April 2010.