Box Jellyfish

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Box Jellyfish : 
  • The Box Jellyfish is also known as the Marine Stinger or Sea Wasp.
  •  A large Box jellyfish contains enough poison to kill 60 adults
  •  The Box jellyfish can kill an adult in four minutes. In some cases the heart slows down or stops almost immediately. It also attacks the respiratory and lymphatic systems. A 38-year-old man was stung near Townsville in Australia, and died in 10 minutes. The box jellyfish has stung many people over the years & not every one who is stung by them dies. Every person reacts differently to poison. Some people can die if they are stung by the bee, others a rattle snake bit seem to not harm them at all. The age of the person where they were stung all effect the time the ability for the poison to work. If you were stung in the throat the toxins would move very quickly through your blood to your heart & brain potentially killing you in minutes, which has happened. Others are stung on the extremities & so the toxins take longer to get to the vital organs. So some people die very quickly while others stay alive for a considerable period of time. And many have survived to tell the tale. Please refer to the link below Marine Medic.
  •  For a fully-grown jellyfish, the bell, or body, can be as large as a basketball, and it might have 60 tentacles up to 3 metres long. However, as it is almost completely transparent, the bell is often difficult to see, and the tentacles are almost invisible.
  •  Each tentacle carries millions of poison capsules called nematocysts. Each one acts like a hypodermic needle injecting its poison directly into the skin. So unlike a venomous snake, which usually bites in one place only, the box jellyfish can inject its poison over a wide area, making it much more difficult to treat.
  •  The nematocysts are only 0.5mm long, and operate mechanically, but they are stimulated by chemicals found on the surface of fish, shellfish and animals. Normally they are curled up inside the tentacle, but when fired they release in 3/1000 of a second.
  •  They can swim in bursts of up to 5 feet per second.Box Jellyfish
  •  70 people are known to have been killed in Australia alone by Box Jellyfish last century. A number have died in Thailand , S.E. Asia region.
  • There are many species of Box Jellyfish around the world. Currently there are over 36 species known around the world. Some have still not been identified.
  •  Antivenom has been available for the last thirty years, but has to be administered quickly in order to be successful.


New Video Footage from Mauritius 2012:


Stories About The Box Jellyfish

Stories About The Box Jellyfish

"Ian recently traveled to Mauritius to find out information on the jellyfish { Invisible } he was killed by." Interviews from people who live in Mauritius.



Ian McCormack's Testimony

Ian McCormack's Testimony

"Ian speaks to the divers and fisherman on the island of Mauritius, and tells of his testimony."



Jane McCormack

Ian's wife Jane talks about her time in Mauritius. Lee Moy from Tamarin Bay shares how she knew Simon who told her that the doctors tore up Ian's death certificate when he came back to like in the hospital.


Mauritian Dive Instructors Experience with one Box Jellyfish in 2006
In 2006 and I was conducting an Open Water Diver Course and lucky I had only one student underwater.I'm an OWSI 622312 from PADI.
Was at 10mts depth at 'Coin De Mire' Island (North of Mauritius,Cap Malheureux) and got stung ,after about 3 minutes the nightmare started, I couldn't breathe, dizziness ,heart beat was about 200+ min and entire body cold, it started from feet to head.
I got stung in the arm and it was like burning, I could feel the heat on my arm and 1st reaction to try to remove something on my arm.
Then I saw the BOX JellyfishA small box 4cm*4cm,transparent with 4 tails of approx 6cm long on each angle at the bottom and I noticed the form from it lighting (Blue and Red).
Only when I surfaced that I came to myself, but the heart beat too long to come to normal.
After 45mins I was ok, but not fit as usual. Then after about 3 hours the heart beat started to raise and problem to breath, I went to hospital and put injection with Antitestamine after informing the doctor that I got stung by a Jelly fish.
But my BP was very high and the doctor himself could not give an answer...
They put me under perfusion but it was the same. When the heart beat increase and problem to breath starts,its really a very very bad sensation.
For 2 yrs doctors could not tell me what was my problem and I had to give up diving, because every time I've tried to dive, impossible. 
And my BP was 17 for 3yrs

Oliver Leung { Vacoas , Mauritius }
Snorkelling in Mauritius
The water is so clear I can count all my toes and other people's too! You can snorkel just about anywhere, one thing though, cover your back with plenty of waterproof suncream, my brother was so busy following the fishes his back got badly burnt. the south is best for marine near Le morne, the north is also brilliant, watch out for jelly fish, ask the locals about them as they are poisonous,good thing they are mostly out at night. Most hotels can give advice.


Jellyfish Watch Mauritius :


Box Jellyfish in Mauritius

Date of Sighting: 09/05/2009
Description: I was on holiday in Grand Bay (North) Mauritius and on my last night on the island I planned a night swim. I got about knee-deep in the water and changed my mind for some reason. Later that night, we were walking along the beach and started seeing many small rectangular shaped jellyfish being washed up along the beach. One of the guys I was with, said that it was a boxjelly fish but I wasnt convinced as it just didnt make sence. I Googled them as soon as I got back to South Africa and and saw that they were indeed Box Jellyshish (an unusual place for them to be) and accuratly timed according to lunar predictions - about 12 days after the full moon?!
Organism: Box Jelly
Quantity: 11 to 99
Mauritius : Health  & Safety:
Health and safety
A holiday in Mauritius is usually trouble free. Generally, Mauritians are friendly and honest people, but being in a foreign place, you should take a few basic precautions.
Personal Safety
Petty crime can be a problem and it is not advisable to roam around alone at night outside the grounds of hotels.
If you are shopping in Port Louis Central Market, then you should take care of pick pocketing. Always take proper care of your bags and valuables while visiting popular tourist destinations such as Pereybere, Grand Baie, Flic en Flac and Tamarin. Beware of taxi drivers if they have some excuse for not taking you to your desired destination as they might want to direct you to a destination from where they could earn a commission and therefore you would end up spending more.
You should contact few locals and learn about all the places, taxi fares and commodity rates so that you don’t get cheated.
Medical Safety
The visitors travelling to Mauritius don’t need any vaccination certificates for entering into Mauritius, unless they are travelling from a country infected by yellow fever.
It’s ideal to pack shoes that are suitable for wearing in the sea to protect against sharp coral, sea urchins and stonefish. Stonefish or Jellyfish stings are very rare but can be fatal in some cases. You should obtain immediate medical attention if stung. Many hotels in Mauritius provide anti-venom serum.
You should take precautions against mosquito bites, as there have been several cases of the Chikungunya virus, which is spread by mosquito bites. Malaria has been quarantined in Mauritius, so you need not fear it. If you are travelling from a country like India, Pakistan, Nepal, etc. then you would need to take a blood test within 2-3 days of your arrival for Malaria. If found infected, you would be required to go back to your country immediately.
Travelers’ diarrhea is the most common disease in Mauritius and thus, you should always go for packed mineral water. Diarrhea mostly has its concurrence with vomiting and nausea. There can be fever as well as blood in the stool. Medicines can be had after consultation with the local doctor.
Medical facilities are good and free in public hospitals compared to private clinics that are expensive and medical insurance is recommended there.
Service Aide Medicale Urgence or the SAMU is one of the organizations under the government of Mauritius that offer emergency services to the guests. Another private organization that offers emergency assistance to the visitors is MegaCare.
Numbers that might be very useful in case of an emergency are Service Aide Medicale Urgence – 114 and MegaCare – 116.

Marine Medic : Facts from Australia on the amount of box jellyfish stings that have occured between 1970 - 1997


Box jellyfish (class Cubozoa) are cnidarian invertebrates distinguished by their cube-shaped medusae. Box jellyfish are known for the extremely potent venom produced by some species. Chironex fleckeri, Carukia barnesi and Malo kingi are among the most venomous creatures in the world. Stings from these and a few other species in the class are extremely painful and sometimes fatal to humans.



[edit] Nomenclature

"Box jellyfish" or "sea wasp" is also a common name for the notoriously dangerous Chironex fleckeri. The ambiguous but commonly used terms "sea wasp" and "marine stinger" are sometimes used to refer to the more venomous species of box jellyfish.

[edit] Anatomy

"Cubomedusae", from Ernst Haeckel's Kunstformen der Natur, 1904

Box jellyfish most visibly differ from the "true" or Scyphozoan jellyfish in that they are umbrella shaped, rather than domed or crown-shaped. The underside of the umbrella includes a flap, or velarium, concentrating and increasing the flow of water expelled from the umbrella. As a result, box jellyfish can move more rapidly than other jellyfish. In fact, speeds of up to six metres per minute have been recorded.[1]

The box jellyfish's nervous system is also more developed than that of many other jellyfish. Notably, they possess a nerve ring around the base of the umbrella that coordinates their pulsing movements; a feature found elsewhere only in the crown jellyfish. Whereas some other jellyfish do have simple pigment-cup ocelli, box jellyfish are unique in the possession of true eyes, complete with retinas, corneas and lenses. Their eyes are located on each of the four sides of their bell in clusters. These enable them to see specific points of light, as opposed to simply distinguishing between light and the dark. Box jellies also retain the lesser type of eye, because the strong eyes are only one of four subsets.[2]

[edit] Distribution

Although the notoriously dangerous species of box jellies are largely, or entirely, restricted to the tropical Indo-Pacific, various species of box jellies can be found widely in tropical and subtropical oceans, including the Atlantic and east Pacific, with species as far north as California, the Mediterranean (e.g., Carybdea marsupialis)[3] and Japan (e.g., Chironex yamaguchii),[4] and as far south as South Africa (e.g., Carybdea branchi)[5] and New Zealand (e.g., Carybdea sivickisi).[6]

[edit] Defense and feeding mechanisms

Box jellyfish warning signpost at a Cape Tribulation beach in Queensland, Australia
Jellyfish/stinger net exclosure at Ellis Beach, Queensland

The box jellyfish has been called "the world's most venomous creature,"[7] though only a few species in the class have been confirmed to be involved in human deaths and some species pose no serious threat. For example, the sting of Chiropsella bart only results in short-lived itching and mild pain.[8]

Each tentacle has about 500,000 cnidocytes, containing nematocysts, a harpoon-shaped miscroscopic mechanism that injects venom into the victim.[9] In Australia, the fatal envenomations are most often perpetrated by the largest species of this family of jellyfish Chironex fleckeri, owing to the high potency of the venom carried in their nematocysts. The recently discovered and very similar Chironex yamaguchii may be equally dangerous, as it has been implicated in several deaths in Japan.[4] It is unclear hence which of these species is the one usually involved in fatalities in the Malay Archipelago.[4][10] In 1990 a 4-year-old child died after being stung by Chiropsalmus quadrumanus at Galveston Island in the Mexican Gulf, and either this species or Chiropsoides buitendijki are considered the likely perpetrators of two deaths in West Malaysia.[10] At least two deaths in Australia have been attributed to the thumbnail-sized Carukia barnesi.[11] Those who fall victim to C. barnesi may suffer severe physical and psychological symptoms known as Irukandji syndrome.[12] Nevertheless, most victims do survive, and out of 62 people treated for Irukandji envenomation in Australia in 1996, almost half could be discharged home with few or no symptoms after 6 hours, and only two remained hospitalized approximately a day after they were stung.[12]

In Australia, C. fleckeri has caused at least 64 deaths since the first report in 1883,[13] but even in this species most encounters appear to only result in mild envenoming.[14] Most recent deaths in Australia have been in children, which is linked to their smaller body mass.[13] In April 2010, a 10 year old Australian girl survived multiple stings from box jellyfish and her survival is considered a medical miracle.[15] In parts of the Malay Archipelago, the number of lethal cases is far higher (in the Philippines alone, an estimated 20-40 die annually from Chirodropid stings), likely due to limited access to medical facilities and antivenom, and the fact that many Australian beaches are enclosed in nets and have vinegar placed in prominent positions allowing for rapid first aid.[14][16] Vinegar is also used as treatment by locals in the Philippines.[10]

The box jellyfish actively hunts its prey (zooplankton and small fish), rather than drifting as do true jellyfish. It is capable of achieving speeds of up to 4 knots (1.8 m/s).[citation needed]

Box jellyfish are known as the "suckerpunch" of the sea not only because their sting is rarely detected until the venom is injected, but also because they are almost transparent.[17]

The venom of cubozoans is distinct from that of scyphozoans, and is used to catch prey (fish and small invertebrates, including shrimp and bait fish) and for defense from predators, which include the butterfish, batfish, rabbitfish, crabs (Blue Swimmer Crab) and various species of sea turtles (hawksbill turtle, flatback turtle). Sea turtles, however, are apparently unaffected by the sting and eat box jellies.

In northern Australia, the highest risk period for the box jellyfish is between October and May, but stings and specimens have been reported all months of the year. Similarly, the highest risk conditions are those with calm water and a light, onshore breeze; however, stings and specimens have been reported in all conditions.

In Hawaii, box jellyfish numbers peak approximately 7 to 10 days after a full moon, when they come near the shore to spawn. Sometimes the influx is so severe that lifeguards have closed infested beaches, such as Hanauma Bay, until the numbers subside.[18][19]

[edit] Taxonomy

As of 2007, at least 36 species of box jellyfish were known, grouped into two orders and six families.[20] A few new species have been described since then, and it is likely undescribed species remain.[4][5][8]

Class Cubozoa

The Medical Journal of Australia {MJA 1996: 165:658 }

Worldwide deaths and severe envenomation from jellyfish stings

Peter J Fenner and John A Williamson

From our database of fatal and serious human envenomations, we report several cases, look at the distribution of these events, and discuss treatment.

MJA 1996; 165: 658

Readers may print a single copy for personal use. No further reproduction or distribution of the articles in whole or in part should proceed without the permission of the publisher. For copyright permission, contact the Australasian Medical Publishing Company
Journalists are welcome to write news stories based on what they read here, but should acknowledge their source as "an article published on the Internet by The Medical Journal of Australia ".

Introduction - Distribution of jellyfish and reported envenomations - Sting seasons - Reflections on treatment - Applying vinegar - Removing adherent tentacles - The role of steroid therapy - Chironex fleckeri antivenom - Conclusions - Acknowledgments - References - Authors' details

Register to be notified of new articles by e-mail - Current contents list - ©MJA1996


We have collected worldwide information about jellyfish and their stings since 1990, through personal communication with members of the International Consortium of Jellyfish Stings (ICJS), 1 investigating reports of serious jellyfish stings heard on the "grapevine", and travelling in areas of chirodropid (multitentacled "box" jellyfish) distribution. Annual reports of our data have been published from 1991 to 1993. 2

Our database now records over 1100 individual cases of stings (some severe and fatal), as well as some 1000 monthly reports of jellyfish numbers and stings, from surf life saving clubs in Queensland over the past six years. Our data are only the "tip of the iceberg" and probably an inadequate indication of the extent of the problem worldwide. However, we continue to seek information, now also by internet and e-mail.

Our data include information on envenomation by Physalia , the Portu guese man-o'-war or bluebottle. Although not a true jellyfish (actually a siphonophore, or hydroid colony), it stings like one, is popularly regarded as one, and we treat it as one in this article.

A brief description of the mechanism of a jellyfish sting is provided in Box 1. While many suspected deaths from envenomation, and the jellyfish species involved, remain inadequately authenticated, documented deaths from jellyfish stings usually involve species of chirodropid, 5,6 described and shown in Box 2.

In this article we examine the distribution of serious and fatal jellyfish envenomations (illustrated in the Map), the animals involved and aspects of treatment, and we describe some previously unreported cases (Table).


Distribution of jellyfish and reported envenomations

Australia In Australia, particularly on the east coast, up to 10 000 stings occur each summer from the bluebottle (Physalia spp.) alone, with others also from the "hair jellyfish" (Cyanea) and "blubber" (Catostylus). More bluebottle stings occur in South Australia and Western Australia, as well as stings from a single-tentacled box jellyfish, the "jimble" (Carybdea rastoni) (personal data) .

The chirodropid Chironex fleckeri 3,4,8 is known to be the most lethal jellyfish in the world, 3 and has caused at least 63 recorded deaths in tropical Australian waters off Queensland and the Northern Territory since 1884. 3

Indo-Pacific region

The presence of chirodropids has now been confirmed in the tropical Indo-Pa cific ocean from the Maldive Islands 9-12 in the west, eastwards to the Philippines, north to Amani Island, Japan (see below), and south to tropical Australia; this includes Brunei, Sarawak, Sabah (L Marsh, Curator of Marine Invertebrates, West Australian Museum, 1993, personal communication), Papua New Guinea, the Malaysian archipelago, Gulf of Thailand, 8 Java and southern India. 12

Deaths have previously been reported from Penang (Malaysia), the Philippines, Bougainville Island, the Solomon Islands, "North Borneo" (now Sarawak, Brunei, Sabah), and Papua New Guinea (d'Entrecasteaux Islands). 8

Medical officers at the Labuan District Hospital (in Malaysia) have been quoted as saying that there are two to three deaths there each year from jellyfish stings and another one or two victims who survive, but require intensive care and commonly remain unconscious for 12-24 hours. 13

The Americas

Chirodropids have been described in waters along the eastern coast of the Americas between the Tropics, including the waters around many Caribbean islands. 11,14 Serious stings from these chirodropids have also been reported from beaches in Puerto Rico during the summer months (B Cutress, Associate Investigator, Marine Biology Department, Puerto Rico University, 1992, personal communication).

In 1990, a 4-year-old boy at Galveston Island, in the Gulf of Mexico, was stung and died within 20 minutes, despite cardiopulmonary resuscitation. 6 Stinging cells were identified as being from a chirodropid previously described in that region. 14

Three fatal envenomations from Physalia physalis have been reported from Florida and North Carolina, in the United States. 15,16 Serious envenomations have also been reported from both sides of the Atlantic. 17-19


Apart from Physalia species and chirodropids, the only other jellyfish presently known to cause deaths in humans are large specimens (up to 1 m diameter) of Stomolophus nomurai (Mingliang, Research Assistant, Qingdao Hospital, 1991, personal communication), a jellyfish found in the Yellow Sea between China and South Korea. Reports of eight deaths have now been published, five in detail. 20,21 Victims die with acute pulmonary oedema some 2-24 hours after the initial envenomation.


A chirodropid occurs in the tropical oceans of west Africa, 22,23 but we know of no published reports of deaths or serious stings. Although chirodropids have not been reported to occur on the eastern tropical coastline of Africa, they must be expected in these waters.

South India and Sri Lanka

Serious jellyfish envenomations occur in the Indian region, with peripheral ischaemia reported in at least two victims. 24,25 Although the jellyfish is frequently unidentified, chirodropids, Sanderia and Physalia species occur in this region.

Two fatalities were reported recently on the eastern side of the Indian Ocean, on Langkawi Island, a tourist resort in Kedah, a northern state of Malaysia. From the rapid demise of the victims, and appearance of sting marks, they probably died of chirodropid envenomation (Dr Iekhsan Othman, Malaysia, personal communication). 12

Sting seasons

In the Southern Hemisphere, chirodropid stings occur mainly in the summer months (December-May), 3 but over a longer season in areas closer to the Equator. In the Northern Territory stings have occurred in every month, with deaths in all months except July. 3,4,8 Chirodropids may occur only in December and January at the southern extreme of their recorded range (just north of Bundaberg, Queensland). 3

In the northern area of Borneo (Northern Hemisphere), stings usually occur in the dry hot season, from March to July, when seas are calm.

Reflections on treatment

Applying vinegar Two to 10 per cent acetic acid in water was recommended as a first-aid treatment for Chironex fleckeri nematocyst inhibition by Hartwick et al. in 1980. 26 Household vinegar has been a traditional treatment for box jellyfish stings in the Philippines since the turn of the century, although other "traditional" treatments were also used. Fishermen in Kukup also describe stings from cubozoan jellyfish in Malaysia as being treated with vinegar (P J F, personal observation, 1987). We do not know how long this remedy has been used.

In two cases recorded on our database ( Table, Cases 3 and 7), victims seemed to stop breathing after vinegar was poured on the envenomed area. Whether this was a cause-related effect is not known; further research is needed.

Removing adherent tentacles

In another of our cases ( Table, Case 5), removal of the adherent tentacle material was accompanied by impairment of consciousness. Our advice has been for the rescuers to remove the tentacles physically with fingers, if vinegar is unavailable, before applying any compression bandages. 3 While this single report scarcely invalidates such advice, further case studies and research are awaited.

The issue of removing adherent tentacle material in any jellyfish (especially serious chirodropid) stinging is complex. Fully extended tentacle material presents most of the nematocysts to the victim's skin, 27 and most will have discharged by the time adherent tentacles on the skin are being dealt with by the first-aiders. However, even partial contraction of tentacle material protects some nematocysts from discharge upon contact, 27 and the response of chirodropid tentacles to sudden entanglement with a human victim seems likely to involve at least some immediate tentacular contraction. Consequently, it seems probable that some nematocysts in adherent tentacle material will remain undischarged, and inappropriate stimulation could result in additional venom being injected into an already seriously envenomed person.

If tentacles have not been inactivated with vinegar, 26 it would seem prudent to carefully, but promptly, "pick them off" the patient's skin with minimal handling, and no rubbing, before applying either compression bandages (in the case of serious chirodropid stings) or analgesic cold packs (for use in chirodropid or other cnidarian stings). Applying compression bandages directly over untreated adherent tentacle material cannot be recommended. However, once tentacles have been doused with vinegar for a minimum of 30 seconds, no time should be lost in removing them before applying bandages. 3

One of our cases (Table, Case 3) describes papilloedema after a chirodropid sting. This is the first such observation published, although Heazlewood (personal communication, 1992) reports a case of cerebral oedema in a 4-year-old in Cairns in 1980, after an "irukandji" (the carybdeid Carukia barnesi ) sting.

The role of steroid therapy

Steroid creams may be useful for mild itching in the immediate healing period after a cubozoan sting, 27 although Burnett 3 now doubts their efficacy. Systemic steroids should be used for severe cases of delayed hypersensitivity, given as prednisone (0.5-1 mg/kg body weight, daily), until the symptoms are fully controlled -- usually just a few days. After such a short course, it is unnecessary to taper the dose.

Chironex fleckeri antivenom

The exact mechanism of action of Chironex fleckeri venom and antivenom remains incompletely understood, despite several studies. 28,29 The efficacy of Chironex fleckeri antivenom in stings from the Australian chirodropid named Chiropsalmus quadrigatus is also unclear -- as is the exact identification of this species. 3 An early study showed in-vitro neutralisation of the dermatonecrotic, haemolytic and lethal factors of the venom of this Australian species when Chironex antivenom was used. However, although passive immunisation of mice with the antivenom reduced dermato necrosis, it did not protect against the lethal effects of Chiropsalmus quadrigatus venom. 30 Another study, using rabbit antisera prepared against Chironex fleckeri venom, showed no in-vitro cross- protection against the venom of Chiropsalmus quadrigatus . 31 However, the Commonwealth Serum Laboratories (CSL) currently recommends the use of Chironex antivenom for severe envenomation from the Australian " Chiro psalmus quadrigatus ".

The possible benefits of Chironex antivenom for severe envenomations by chirodropids worldwide need investigation. Chironex antivenom has been shown to be of little benefit in the "irukandji" syndrome (it neither relieves the pain of envenomation nor reduces any other systemic problem), 32 and is currently not recommended for envenomation from any other (non-chirodropid) jellyfish species.


Lethal, or potentially lethal, chirodropid jellyfish occur worldwide, around every major land mass in the tropical and some subtropical oceans, and deaths and serious morbidity are more common than previously believed. Physicians practising in these areas, or those advising people who travel to such areas, must be aware of the problem, and advise their patients on awareness, prevention and treatment (summarised in Box 3) of potentially lethal jellyfish envenomation. The toxicology of the venoms needs further study.

Corner of Palmer and Grendon Streets, North Mackay, QLD.
Peter J Fenner, FACTM, FRCGP, General Practitioner and Marine Stinger Officer, Surf Life Saving Queensland Inc.
Hyperbaric Medicine Unit, Department of Anaesthesia and Intensive Care, Royal Adelaide Hospital, Adelaide, SA.
John A Williamson, FANZCA, FACTM, Director and Associate Professor.
No reprints will be available. Correspondence: Dr P J Fenner, PO Box3080, North Mackay, QLD 4740.


Box Jellyfish: National Geographic


Photo: A box jellyfish beneath the water's surface                                 The box jellyfish's venom is among the most deadly in the world, containing toxins that attack the heart, nervous system, and skin cells. Photograph by David Doubilet Map  Map: Jellyfish range Box Jellyfish Range Fast Facts                       Type: Invertebrate Diet: Carnivore Average life span in the wild: Less than 1 year Size: 10 ft (3 m) long; 10 in (25 cm) across Weight: Up to 4.4 lbs (2 kg) Group name: Fluther or smack Did you know? Sea turtles are unaffected by the sting of the box jellyfish and regularly eat them. Size relative to a 6-ft (2-m) man:Illustration: Box jellyfish compared with adult manThe infamous box jellyfish developed its frighteningly powerful venom to instantly stun or kill prey, like fish and shrimp, so their struggle to escape wouldn’t damage its delicate tentacles. Their venom is considered to be among the most deadly in the world, containing toxins that attack the heart, nervous system, and skin cells. It is so overpoweringly painful, human victims have been known to go into shock and drown or die of heart failure before even reaching shore. Survivors can experience considerable pain for weeks and often have significant scarring where the tentacles made contact. Box jellies, also called sea wasps and marine stingers, live primarily in coastal waters off Northern Australia and throughout the Indo-Pacific. They are pale blue and transparent in color and get their name from the cube-like shape of their bell. Up to 15 tentacles grow from each corner of the bell and can reach 10 feet (3 meters) in length. Each tentacle has about 5,000 stinging cells, which are triggered not by touch but by the presence of a chemical on the outer layer of its prey. Box jellies are highly advanced among jellyfish. They have developed the ability to move rather than just drift, jetting at up to four knots through the water. They also have eyes grouped in clusters of six on the four sides of their bell. Each cluster includes a pair of eyes with a sophisticated lens, retina, iris and cornea, although without a central nervous system, scientists aren’t sure how they process what they see.
The map above shows the areas of main concentration of the Box Jellyfish, Box Jellyfish of varying types and in turn strength of venom are found around Australia, the Philippines, off the Indonesian Coast, Hawaii, Vietnam, the Caribbean and other tropical areas including off the coast of Africa and the Indian Ocean Islands.
The sting of box jellyfish found in Hawai`i, Carybdea alata and Carybdea rastonii, is very painful and can even cause anaphylactic shock in some individuals. Box Jellyfish Carybdea alata and Carybdea rastonii, regularly "swarm" to Hawaii's Leeward shores 9 to 10 days after the full moon. Carybdea alata cause the most "trouble" for humans here.
[Tamanaha RH and Izumi AK. Persistent cutaneous hypersensitivity reaction after a Hawaiian box jellyfish sting (Carybdea alata). J Amer Acad Dermatol. 1996 Dec;35(6):991-3.]

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