BOX JELLYFISH Chironex fleckeri

One of the most venomous marine creatures known, the box jellyfish can kill a healthy adult in minutes. This jellyfish is found in northern Australian waters and has caused more than 70 deaths here since 1883. It has an LD of 0.272. As well as haemo50 toxins and neurotoxins, the venom contains dermatonecrotic substances, which cause skin-scarring. Venom is delivered by millions of tiny, harpoon-like stinging cells on up to 60 tentacles, and an encounter is said to be excruciating.