Jellyfish are known to be found in almost 200 species throughout our planet’s oceans. Many species have harmless stinging cells, but a few have highly venomous stinging cells that can cause severe pain or even death if humans come into contact with them. If you enter the water, be careful of these poisonous jellyfish.
When snorkeling or scuba diving in warm water, even in a warm environment, wear exposure protection. These poisonous jellyfish pose many severe health risks to humans, so victims must always seek immediate medical attention after being stung.
Do you know why box jellyfish are so deadly?
As a result of their relative anatomical sophistication, box jellyfish are the deadliest jellyfish. While they do not have a brain, they do have a complex nervous system which allows them to propel themselves through the water and swim fast.
Jellyfish Species That Are Poisonous & Deadliest
The following jellyfish species are incredibly dangerous to humans, in contrast to other (occasionally) stinging jellyfish. Their transparent bodies can make it difficult to spot these jellyfish. If possible, avoid swimming in those waters and be aware of the places where they may frequent.
Keep a jellyfish first aid kit (which should definitely include vinegar) on hand if you must go near their natural habitats. If you are stung, make arrangements to be taken to the nearest hospital immediately.
Keep your sting dry by not peeing on it.
1.Chironex Fleckeri jellyfish (Sea Wasp)
Sea wasps, also known as Chironex fleckeri, are some of the deadliest jellyfish species. Despite being nearly invisible, this box jellyfish can be very difficult to locate. Shallow waters and daytime hunting are also preferred by them. In addition, this increases their chances of coming into contact with beachgoers who are swimming.
A single grain of salt is enough to kill an adult man with the venom of the Chironex fleckeri, the strongest venom of any jellyfish. In severe cases, stings can result in excruciating pain and burning sensations and, if left untreated, lead to cardiac arrest and death.
It has been attributed to 63 human deaths in Australia over the course of 80 years, making it the deadliest jellyfish in the world. That’s just a sample of the cases we’re aware of.
With its pale blue, transparent color and four-cornered, bell-shaped head, a sea wasp or a similarly dangerous box jellyfish can be identified. Tentacles can grow up to 10 feet long on each corner of its bell head. The Indo-Pacific region and Australia and New Guinea are the only places where you can find this extremely poisonous jellyfish.
Characteristics and Features:
A potentially fatal sting with extreme power and potency
A pale blue, transparent color
Cube-like, bell-shaped head
Up to 10 inches wide and 10 feet long
Tentacles grow from each corner of the bell up to 15 in number
Throughout the Indo-Pacific, it is found off the coast of North Australia
2.Chiropsalmus Quadrigatus jellyfish
Box jellyfish of this species resemble Chironex fleckeri, but are smaller. Its diminutive size doesn’t deter it from packing a punch. Oceans of the Indo-Pacific and Western Atlantic are home to these animals. Japan’s Okinawa Prefecture calls them “habu,” and these creatures are often encountered by people there.
Certain cases can be fatal due to the sting of Chiropsalmus Quadrigatus. Heart attacks, respiratory failure with acute pulmonary edema, or death are dangerous effects of its sting. It has seven long, flat tentacles growing from each of its four appendages, including an appendage that looks like a hand.
Fish are more likely to be caught by its unusual tentacles than crustaceans and other jellyfish that normally prey on round-tentacled species.
Characteristics and Features:
The stings are extremely painful
Tentacles resemble ribbons and are transparent
3.7 inches wide and 4.3 inches high
On each corner of the bell, it grows up to nine flat, long tentacles
They are found in the Western Atlantic and Indo-Pacific oceans
3.Irukandji jellyfish
The tiny Irukandji is another jellyfish that does not play around when it comes to its venomous sting. Once only in Australian waters, recent sightings have been in Florida, Japan, Thailand, and even in the British Isles—which has led to growing concern over the possible global spread of this fatally poisonous jellyfish.
Its small size—about the size of an adult fingernail—and nearly transparent body makes it an incredible threat to humans, who will in most cases feel the burn without ever having seen their attacker. A sting from the Irukandji produces what is known as Irukandji Syndrome, from which the victim will feel severe pain that can last for up to 12 hours; burning sensations on the skin; nausea and vomiting; excruciating stomach cramps, as well as muscle cramps in the legs and arms; serious cardiac problems; and a strange psychological symptom that causes the victim to experience feelings of impending doom, which makes them actually beg for death. “Patients believe they’re going to die and they’re so certain of it that they’ll actually beg their doctors to kill them just to get it over with,” said Australian biologist Lisa Gershwin during an ABC radio interview in 2007.
Nonetheless, a sting by an Irukandji is not an immediate death sentence. While it is without a doubt one of the most dangerous jellyfish species in the world, people typically survive the sting with swift and proper treatment—and plenty of pain medication.
Characteristics and Features:
The stings of these insects are powerful, venomous, and not immediately noticeable
The size of an inch and the height of a meter
Tentacles and bell fire stings
In the water, nearly invisible and transparent
A warm-water fish that lives along the coast and on coral reefs
4.Morbakka Fenneri jellyfish
There is a jellyfish in Queensland’s waterways and marinas known as Morbakka fenneri, which is known for its powerful sting. Northerly waters are preferred by them. The jellyfish is a bit larger than the other jellyfish on this list and belongs to the box jellyfish family. On top of a solid body with pink, wart-like protrusions, it measures roughly four inches long and has a two-inch bell diameter.
Morbakka fenneri stings are usually identifiable by their larger size, so most people can find the source if they get stung. Several severe cases of Irukandji Syndrome have been associated with the stings, but they are rarely life-threatening.
Characteristics and Features:
Irukandji syndrome can be caused by this powerful sting
Having a large warty body, this bell is transparent and box-shaped
Four flat tentacles that resemble ribbons
A maximum of 2 inches wide and 4 inches high
Australia’s eastern and northern warm waters are home to this species
5.Alatina Alata jellyfish
The Alatina alata is also known as a sea wasp and is another type of box jellyfish. Known for swarming along the beaches of Pakistan in the Arabian Sea and off the coasts and bay areas of Hawaii and other parts of the Pacific, it is also known as Carybdea alata. This species has a milder sting than the others we’ve discussed so far. There may be some discomfort and unpleasantness, however.
Alatina alata sting victims can apply cold or hot treatments to reduce pain and swelling after being stung by the insect. The sting can, however, cause Irukandji Syndrome due to its classification as a box jelly, so it is important to stay vigilant and seek medical attention immediately when stung.
Characteristics and Features:
There is severe, immediate pain associated with stings
Box-shaped bell with a transparent and glassy appearance
A maximum of six inches in width and twelve inches in height
The tentacles are pinkish-yellow and long
Pacific and Atlantic oceans are home to this species
What to do if you’re stung by a jellyfish?
Jellyfish stings should be rinsed with vinegar and tentacles should be removed if visible. Let the skin soak in hot water for a few minutes. A deadly jellyfish sting should be treated as soon as possible by getting out of the water and rinsing the area with acetic acid. Call for emergency services as soon as possible after removing any visible tentacles.
How to avoid box jellyfish
This deadly jellyfish can be prevented from stinging you by:
When spotting box jellyfish, stay away from the water
When walking along the shore or in shallow water, wear water shoes
When you are in the water, wear a wet suit or skinsuit
Whenever you go swimming, always keep a medical kit handy