Nycticebus kayan is less than a foot long and weighs less than a pound.
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Ch'ien C. Lee /
Cute But Deadly
Researchers have found a species of slow loris with a poisonous bite

By Jennifer Marino Walters | for  

It has huge eyes, a tiny body, an adorable furry “face mask”—and a deadly bite. It’s the Nycticebus kayan, a new species of slow loris discovered on the island of Borneo in Southeast Asia.

The cute creature is named after the Kayan River, a major waterway that flows through the region. The loris is less than a foot long and weighs less than a pound. The fuzzy discovery is helping to highlight the amazing variety of animal species in the jungles of Borneo and nearby islands.

Slow lorises are nocturnal animals that live throughout Southeast Asia. A nocturnal animal sleeps during the day and is active at night.

N. kayan is the only loris known to have a toxic bite. The creature’s toxin is first made near its elbows. The N. kayan licks its elbow to mix the toxin with saliva, which activates the poison. It then bites its victim. The animal also covers the fur of its babies with the toxin to protect them from predators.

Researchers identified the N. kayan based on differences in the facial markings of each species. Four species of slow loris are now known to live in Borneo. The N. kayan has highly contrasting black-and-white face markings, with dark patches around its eyes. The other species’ markings are more blended and have less contrast.


Bornean slow loris populations may be in trouble. Like other animals on Borneo and nearby islands, they face threats from human activity, which can result in habitat loss. One third of Borneo’s forests have been cleared in the past 25 years.

“In addition to habitat loss [from] deforestation, there is a booming black-market demand for the animals,” says Rachel Munds, a researcher at the University of Missouri. “They are sold as pets, used as props for tourist photos, or [used] in traditional Asian medicines.”

But the discovery of the new loris species has called attention to these special animals. It may prompt local authorities to beef up legal protections for the creature so that it does not disappear forever.