User:Corgsi05/Chironex fleckeri

Description
Chironex fleckeri lives on a diet of prawns and small fish, as well as crabs and other pelagic invertebrates. Their known predators include green sea turtles and leatherback turtles, whose thick skin is impenetrable to the cnidocytes of the jellyfish, among other pelagic predators.

Sting
Chironex fleckeri is best known for its extremely powerful "sting". The sting can produce an excruciating pain accompanied by an intense burning sensation, like being branded with a red hot iron. '''Stings may also result in white welts and lines that may be accompanied by blistering. In some cases, the sting can cause permenant damage or death to the skin and result in scars.' Fatalities are most often caused by specimens of C. fleckeri'' that are larger than 15 cm (5.9 in). If left untreated, large amounts of venom injection can cause fatality in 5 minutes.

In Australia, C. fleckeri has caused at least 64 deaths since the first report in 1883, but most encounters appear to result only in mild envenomation. Among 225 analyzed C. fleckeri stings in Australia's Top End from 1991 to 2004, only 8% required hospital admission, 5% received antivenom and there was a single fatality (a 3-year-old child). 26% experienced severe pain, while it was moderate to none in the remaining. Most deaths in recent decades have been children, as their smaller body mass puts them at a higher risk of fatal envenomation. When people do die, it is usually caused by a cardiac arrest occurring within minutes of the sting. It takes approximately 3 metres (10 ft) of tentacle to deliver the fatal dose.

The venom causes cells to become porous enough to allow potassium leakage, causing hyperkalemia, which can lead to cardiovascular collapse and death as quickly as within two to five minutes with an LD50 of 0.04 mg/kg. It was postulated that a zinc compound may be developed as an antidote. Occasionally, swimmers who get stung will undergo cardiac arrest or drown before they can even get back to the shore or boat.

'''In many cases, there will be a reaction that takes place days after the initial sting if the victim survives. This extremely itchy rash can last weeks after the initial sting. If the skin in the affected area is intact, certain creams and antihistamines may help to alleviate the symptoms.'''

Chironex fleckeri and other jellyfish, including the Irukandji (Carukia barnesi), are abundant in the waters of northern Australia during the warmer months of the year. They are believed to drift into estuaries to breed. Signs like the one pictured are erected along the coast of North Queensland to warn people of such, and few people swim during this period. Some people still do, however, putting themselves at great risk. At popular swimming spots, net enclosures are placed out in the water wherein people can swim but jellyfish cannot get in, keeping swimmers safe.

Reproduction
Chironex fleckeri is capable of both sexual and asexual reproduction and are oviparous.

Sexual Reproduction
A fully grown and sexually mature Chironex fleckeri medusa will begin trying to find a mate in the spring season. Usually, the jellies will move from their usual habitat to a freshwater river for this hunt. If a mate is located, sperm and eggs are expelled into the water by the male and female respectively to result in fertilization. The gametes produced by the spawning process will go on to become planulae and eventually small sea wasp polyps. They will use their two tentacles to hide away from predators by hooking onto a hidden surface and feeding on plankton. The parent organisms die shortly after reproduction occurs.

Asexual Reproduction (Budding)
Polyps created through spawning will begin to form entirely new clones of themselves through a process called budding. The original polyp along with the new ones will eventually become small medusa through metamorphosis and return to the ocean until they are mature. The process will then repeat once they can sexually reproduce and go back to a river to find a mate.