BLUE-RINGED OCTOPUS Hapalochlaena spp.

Although no bigger than an open hand, a blue-ringed octopus has an LD rating 50 of 0.3 for some elements of its venom. One bite contains enough neurotoxins to paralyse many people. They are responsible for at least two known deaths in Australia prior to the 1960s. A bite can induce muscle weakness, breathing difficulties and paralysis within 10 minutes. Death can occur rapidly unless CPR is performed swiftly. There’s no antidote and bites sometimes go unnoticed. It’s found in tide pools and coral reefs in Indo-Pacific waters.