The blue-ringed octopuses (genusHapalochlaena) are three (or perhaps four) octopusspecies that live in tide pools and coral reefs in the Pacific and Indian Oceans, from Japan to Australia. Their primary habitat is around southern New South Wales, South Australia, and northern Western Australia. They are recognized as one of the world's most venomous marine animals. Despite their small size, , and relatively docile nature, they are dangerous to humans if provoked and handled, because their venom is powerful enough to kill humans.