Box jellyfish

The box jellyfish are any of the species of jellyfish belonging to the taxonomic class Cubozoa. They are best known as being one of the most lethal jellyfish in the world. It has caused around 64 deaths in Australia, where it is commonly found, since deaths were first recorded in 1883. The amount of venom in one jellyfish is said to be enough to kill 60 humans in one sting. Being stung results in a very large amount of pain and if not treated, the victim can die within three minutes.

Body Design
The box jellyfish is shaped like a cube and has 4 distinctive sides. These jellyfish have been given the common name "box jellyfish" because of their shape. Their body is light blue and transparent and can grow to be 20 centimeters long and weigh 2 kilograms, or 4.5 pounds.

A box jellyfish can have a maximum of 15 tentacles in each corner of the cube, and these tentacles grow to be up to 3 meters or 10 feet long. Each tentacle on the box jellyfish can have up to 5000 nematocysts, which are the stinging cells. The box jellyfish uses its tentacles to catch its prey, like small fish and crustaceans.

The very powerful venom of the box jellyfish is kept inside stinger cells which are designed to release venom when they detect the presence of certain chemicals, and not by touch. This means that if your skin did not release certain chemicals you would be able to touch a box jellyfish and not be stung. Once the stinger cells detect the correct chemicals, like the ones exuded by human skin and fish scales, they instantly inject their venom into their victim.

The box jellyfish is different from many jellyfish because it is equipped with 4 eyes, while many jellyfish have no eyes whatsoever. It is unknown how it can interpret what it sees with its eyes because it has no brain, but it somehow manages to use its eyes with no normal brain and can by sight swim around the smallest objects. The box jellyfish has developed the ability to jet at a speed of 4 knots, or 2.057 meters per second.

Life Cycle
Jellyfish reproduction takes place over several different stages. In the adult box jellyfish, or medusa, reproduces sexually by releasing sperm and eggs into the water, which forms a planula. This larval stage of jellyfish life will hook on to the bottom of a rock or other structure and grow into another stage of jellyfish life, the polyp--which looks like a small sea anemone. During this stage, which can last for several months or years, asexual reproduction occurs. The polyps duplicate themselves and bud, or strobilate, into a higher stage of jellyfish life, called ephyra. The ephyra is what grows into the adult medusa box jellyfish.

Ecology
The Australian box jellyfish is found in the tropical oceans bordering the northern parts of Australia. Their habitat reaches as far south as Exmouth on the west coast, and Bustard Heads on the east coast (just north of Agnes Waters). Chironex fleckeri (a species of box jellyfish) is also found in the waters of the Indo-Pacific region close to Papua New Guinea, the Philippines and Vietnam. Their exact distribution has not been determined yet.

Box jellyfish like to stay at river mouths, estuaries and creeks, especially after rain fall. When the tide rises they tend to move to shallower waters. They dislike deep water and rough seas. They are not found over coral reefs and areas with much sea grass or weeds. The box jellyfish avoid going deep underwater, especially during wet and high tide seasons.

Box jellyfish's diet consists of small fish, prawns, shrimp, and even other species of jellyfish, though they don't greatly affect the populations of these species. Because fish, prawns, and shrimp could easily tear the body of the box jellyfish it has a very potent venom that will kill small prey almost instantaneously, and for defense from predators, some of which are the butterfish, batfish, rabbitfish, crabs (Blue Swimmer Crab) and various species of sea turtles (hawksbill turtle, flatback turtle).

When Humans are Stung
Box jellyfish stings can cause extreme pain in humans. The tentacles adhere to the skin and should never be removed while they are still attached to a living jellyfish, as this can increase damage. The affected area can burn for weeks without proper treatment, and a scar is often left behind. Box jellyfish cause a high number of deaths where they live. The stings from a box jellyfish can be treated by pouring vinegar on the affected areas. Vinegar will kill the tentacles and allow them to be safely removed. If you are ever stung you should seek out professorial help as soon as possible because you would need an antidote to the venom. The stings can potentially cause cardiorespiratory arrest or arrhythmia, so seek out medical assistance quickly.