A monkey that comes out at night and has a bite so poisonous it could kill a human has been discovered by scientists.
The new species, which is a type of slow loris, releases poison from glands at its elbows which it then takes into its mouth.
Their bite can prove deadly because it can cause anaphylactic shock in humans, killing them.
Researchers think the new species, Nycticebus kayan, went undiscovered for so long because it is nocturnal. It is the only primate with a toxic bite.
However, the new monkey, which is more closely related to bushbabies and lemurs than monkeys and apes, is already on the endangered list.
Professor Anna Nekaris, of Oxford Brookes University, led the team of international researchers who made the discovery in Borneo and the Philippines.
She said: "The slow loris might look like a harmless, big-eyed Ewok from a scene in Star Wars, but the animal is actually one of the only poisonous mammals in the world.
"Its toxin can cause death in humans through anaphylactic shock.
"Unknowing humans should stay clear of the toxin, which is released from near its elbows. When threatened, the loris takes the toxin into its mouth and mixes it with saliva."
Prof Nekaris has warned the slow loris, which was largely unheard of outside primatology circles until a few years ago, was under threat.
It sprang to prominence following a YouTube video of a slow loris in a house in Russia having its feet tickled, leading to a demand in keeping the animals as pets.
This in turn has triggered illegal trading in the animal, many of which have their teeth pulled out by traders to stop them biting.
The discovery of the new species is reported in the American Journal of Primatology.