A photo of a slow loris that was released into a protected forest in Sumatra after undergoing medical care. (Photograph: Reza Septian/International Animal Rescue)
Slow lorises are nocturnal primates. They “have a toxic bite, a trait rare among mammals and unique to primates. The toxin is obtained by licking a sexual gland on their arm, and the secretion is activated by mixing with saliva.”
The toxin can cause death by anaphylactic shock in some people.
According to Smithsonian:
That bite, combined with a hiss-like vocalization, sinuous movements, and a distinctive defensive posture in which the loris raises its arms above its head, make the primate look remarkably like a spectacled cobra ready to strike. Which raises the question: Did the loris evolve to mimic poisonous snakes? Yes, [they argued].