box jellyfish

box jellyfish

The Box Jellyfish is a water dweller.
The box jellyfish is found off the coast of Australia, in the Phillipines, Hawaii, Vietname and most tropical areas, where they are rampant in the warm water just offshore.

The Box Jellyfish is known best and most infamous for the venom it injects which is extremely powerful and excruciatingly painful.


The Box Jellyfish


The Chironex fleckeri and the Carukia barnesi (Irukandji) species are amongst the most venomous creatures in the world and the stings from these are not only extremely painful but are often fatal to human beings who come into contact with them when swimming.

Later the jellyfish dissappear during what is the Australian wintertime, when in fact very often the swimmer can’t use the ocean waters because of the temperature.



The brilliant tropical sun seems to pause in its daily routine to warm the beaches of North Queensland, Australia. The creatures that cause such havoc belong to a group of animals related to the jellyfish. When an animal touches the box jellyfish, the nematocysts fire, puncture the victim and eject venom. The venom paralyzes and kills the box jelly’s prey, which are usually invertebrates.

The venom of some box jellies can be deadly to humans as well. The sea wasp possesses the most potent venom of any marine creature.

This box jellyfish is similar to the species responsible for Irukandji Syndrome. His grandfather rushed into the water and pulled the boy out of the water. Long tentacles dangle from the four corners of the sea wasp’s body. Two of the eyes in the set detect only light, giving the animal a sense of direction.
The venom of an adult sea wasp is so powerful that the victim may not even have time to swim to shore. (Image from Cairnsholiday.com.au) (Click image for larger version)
Irukandji Syndrome – The aftermath of a sting


The sea wasp is not the only dangerous box jellyfish off the North Queensland beaches. Throughout the world, 12 to 16 species of box jellyfish cause Irukandji Syndrome. That’s about the width of a pencil easer. The bodies and tentacles of the box jellyfish that cause Irukandji Syndrome are covered with the stinging nematocysts. Only the tentacles of the sea wasp have nematocysts.
Some of his research is devoted to learning how and why the venom is so potent to humans.

“The venom is not targeted to humans,” states Seymour. The venom of the sea wasp is targeted toward a vertebrate nervous system, like ours.
The venom has a direct effect on the heart and causes immediate death to the tissue it contacts. “The venom begins to digest the tissue immediately,” Seymour continues.

The venom of the box jellyfish that cause Irukandji Syndrome has a weaker effect on humans. The fish larva has a vertebrate system but the venom enters the lymphatic system before it reaches the heart. In humans, the venom takes 20 minutes to pass through the lymphatic system and into the heart, but for fish larva the venom directly enters the heart. “The vinegar does not stop the pain or remove the venom,” Seymour states. Vinegar prevents the reminder of the stinging cells from injecting venom into the victim. Afterwards, the victim is taken to the hospital. The doctors are giving victims magnesium to control the pain – the same treatment given to women in labor. Doctors recognized that the labor pain is similar to the pain caused by Irukandji Syndrome. Seymour and his fellow researchers are becoming more accurate with predicting the beginning and the end of the box jellyfish season. In time, the number of causalities from box jellyfish may be reduced to zero.
Vinegar or white vinegar is best poured over the tentacles to deactivate the venom. Transport immediately to the nearest emergency room.
It can be increased all the way to 100,000 units. Reassurance should be given to the patient.