Found exclusively in South and Southeast Asia, slow lorises are the world’s only venomous primates. They’re arboreal—meaning they live in trees—and can be spotted curling up to sleep in branches or using vines and leaves to get around. They typically only come down to the forest floor when they need to defecate.
There are nine species of slow loris. They all belong to the same genus, with each species sharing many similar characteristics and behaviours. The nine species include the Philippine slow loris, Bengal slow loris, greater slow loris, Kayan slow loris, Bangka slow loris, Bornean slow loris, Sumatran slow loris, Javan slow loris, and pygmy slow loris.
These small, nocturnal creatures are characterised by their large, round eyes, which are adapted for night vision. They have compact bodies, short snouts, dense fur, and distinctive facial markings. On average, they measure 20 to 37 centimetres (or 10 to 15 inches) long.
Slow lorises each have a small bare patch under their arm that secretes oil. When they feel threatened, they lick this oil, which combines with their saliva to create a venom strong enough to kill small arthropods and mammals.
Slow lorises are skilled hunters; they use their slow and deliberate movements to catch prey like insects and small vertebrates. They also have a specialised toothcomb—a unique structure created by their bottom front teeth—that they use for grooming and extracting gum from trees.
Slow lorises are generally solitary and territorial animals. They have the ability to stay motionless for long periods, which is how they got their name—observers noted how slow they were compared to other forest-dwelling animals.
True to their name, slow lorises have a relatively slow reproductive rate, with females typically giving birth to one offspring per year after five to six months of gestation. The infant clings to its mother and is nursed for several months before becoming more independent.
Slow lorises contribute to the health and biodiversity of their ecosystems through seed dispersal and insect control. They also serve as indicators of environmental well-being. They are prey for snakes, eagles, and the occasional orangutans, while also preying on smaller animals and keeping the food chain in check. As omnivores, they consume nectar, which is a very important process for ecosystem regeneration, as they inadvertently transfer pollen between flowers. Similarly, as they eat and digest fruit, they spread seeds through their faeces and contribute to the propagation of the forest’s plants.
Without slow lorises, the ecosystems in which they live would not be able to thrive. Protecting these primates is not only crucial for their own survival but also for the overall balance of their habitats.
Read on to learn more about slow lorises and how we can protect them.
What is a slow loris’ scientific name?
Slow lorises belong to the genus Nycticebus. Each species of slow loris has its own specific name.
- Philippine slow lorises, Nycticebus menagensis
- Bengal slow lorises, Nycticebus bengalensis
- Greater slow lorises, Nycticebus coucang
- Kayan slow lorises, Nycticebus kayan
- Bangka slow lorises, Nycticebus bancanus
- Bornean slow lorises, Nycticebus borneanus
- Sumatran slow lorises, Nycticebus hilleri
- Javan slow lorises, Nycticebus javanicus
- Pygmy slow lorises, Nycticebus pygmaeus
Are slow lorises endangered?
Every species of slow loris has a decreasing population, with statuses ranging from vulnerable to critically endangered.
- Vulnerable slow loris species include the Philippine slow loris, Kayan slow loris, and Bornean slow loris.
- Endangered species include the Bengal slow loris, greater slow loris, Sumatran slow loris, and pygmy slow loris.
- The two species considered critically endangered are the Bangka slow loris and Javan slow loris.
Where do slow lorises live?
Slow lorises are found in South and Southeast Asia, often in swampy areas or humid tropical rainforests, though are also known to live in dry forested habitats. Slow lorises live in the trees to escape ground predators and have adaptations to help them thrive among branches and foliage.
Each species is found in a different area of the continent. The smallest species, the pygmy slow loris, is restricted to forests east of the Mekong River, while the larger Sunda slow loris inhabits peninsular Malaysia and the Indonesian island of Sumatra.
The Philippine slow loris inhabits the island of Borneo and the southern Philippine islands.
The Bengal slow loris is native to parts of Bangladesh, China, and Southeast Asia.
The Kayan slow loris is also found on Borneo, as is the Bornean slow loris.
The Bangka slow loris is only found on the small island of Bangka, Indonesia.
The Sumatran slow loris lives only on Sumatra, and the Javan slow loris lives only on the island of Java, Indonesia.
