Box Jellyfish

The most venomous marine animal on Earth/Marine Life

The Australian box jellyfish (Chironex fleckeri) is widely considered the most venomous marine animal. Its bell-shaped body is about 30 cm in diameter, but its 60 tentacles can extend up to 3 meters long. Each tentacle contains about 5,000 stinging cells called cnidocytes. The venom attacks the heart, nervous system, and skin simultaneously, and a severe sting can cause cardiac arrest within minutes. Despite its lethality, the box jellyfish has 24 eyes arranged in clusters of six on each side of its bell.