What is the most poisonous animal in the world? It isn’t the tarantula, nor is it the cobra. If you want the excitement of encountering the most poisonous animal in the world, you need to put on your diving gear and jump into the sea. That’s right, the animal with the strongest venom, that can kill even a robust man in less than a minute, is a jellyfish. It is called the Chironex fleckeri, better known as the sea wasp. But don’t worry! This isn’t the jellyfish we will run into in our Mediterranean Sea, ours only sting from their tentacles.

The sea wasp lives in the warm Australian ocean and South Pacific. It is as beautiful as it is lethal, this jellyfish’s head is as big as a football, underneath which it has 60 tentacles reaching lengths of up to three and a half metres, covered in stingers that leave no escape to its victims. Biology texts inform us that Chironex fleckeri has 96 eyes giving it “spherical” vision that allows it to see everything that swims around it.

In addition to being much larger and more poisonous than the jellyfish in our seas, the sea wasp is also an excellent swimmer. And this is also a unique characteristic, because most of the time, jellyfish allow themselves to be transported by the currents. This characteristic also makes it more dangerous because this animal has aggressive tendencies and it is estimated that every year it kills between 70 and 80 people in Australia alone.

Differently from the poison coming from a snake or spider, the sea wasp does not need to recharge its venom glands after it attacks. A single adult specimen could therefore, hypothetically, kill a hundred people in less than a minute by simply striking or scratching their skin by less than a millimetre.  Just to say that the much feared great white shark, in comparison is a docile pet.

But the sea wasp is not the only dangerous and poisonous fish a diver could encounter in the sea. In this very special hit parade of the most poisonous animals on the planet, the bridesmaids to our sea wasp are another two infamous animals.

In second place is the Hydrophiinae Fitzinger, better known as the sea snake. This reptile is distantly related to the cobra but is much more deadly. There are 57 species, one more poisonous than the next, but they also live, luckily for us, in warm Australian seas. More rarely it can be found in the seas along the eastern African coast. Contrarily to its landbound cousins, the sea snake does not inject its poison with the first bite. This gives some chance of survival to its victims if they are cured in time, even if its venom is very powerful.

The stonefish lives camouflaged on the sea floor in the Red Sea. Its spikes leave no escape

In third place in the list of animals it is better not to fight with when diving, is the famous stonefish, Synanceia verrucosa. An unsociable animal that spends its life camouflaged in the barrier reefs of the Red Sea and in the Pacific waiting to attack its prey. It does not attack divers, but there is the risk that someone touches it, being stung in the hand by its sharp spines. Another good reason why diving instructors always advise to never touch anything when diving. A good rule that helps save the marine environment as well as our health.