The box jellyfish is considered to be one of the most deadliest marine creatures. It sting can kill people almost instantly.
The most deadliest sea creature in the world is the box jellyfish, also known as the sea wasp or marine stinger. This dangerous jellyfish is found off the coast of Australia, in the Philippines, Hawaii, Vietnam and most tropical areas, where they are rampant in the warm water just offshore. It is considered to be the most venomous marine creature and can kill more people that stonefish, sharks and crocodiles combined.
A sting from the box jellyfish can be fatal. The venom is among the most deadly in the world containing toxins that attack the heart, nervous system and skin cells. The sting can result in cardiovascular collapse, in addition to respiratory failure and neuromuscular paralysis, all that can kill you. A sting is so painful that human victims have been known to go into shock and drown or die of heart failure before reaching land. If someone survives the sting they could be in considerable pain for weeks. They will also have scarring where the tentacles have made contact and, since the tentacles can reach up to 10 feet in size, can be quite large, covering a good deal of your body.
The box jellyfish are pale blue and transparent in color. They could have up to 15 tentacles with about 5,000 stinging cells. Ouch!