Geographic Range
Carukia barnesi
can be found along the coastline of Northern Australia, from Broome along the western
side of Australia to Rockhamptom, Queensland on the eastern side. This includes Port
Douglas in North Queensland to the Whisunday Islands near Mackay. It is also found
in the Cairns regions and the Great Barrier Reef.
- Biogeographic Regions
- australian
Habitat
Carukia barnesi
, unlike its congener
Chironex fleckeri
, is typically found in deeper waters along reefs.
- Habitat Regions
- saltwater or marine
Physical Description
The Irukandji jellyfish is a carybdeid cubazoan, which tend to be smaller than the
other type of cubozoa, the chirodropids. Individuals of this species typically reach
25 mm in diameter, however it has been documented at a diameter of 35 mm.
Carukia barnesi
consists of a transparent bell that is cuboidal in shape that narrows slightly towards
the apex. Extending from each of the four corners of the bell is a retractable tentacle
that varies in length from 50 to 500 nm. Both the tentacles, as well as the body,
are covered in stinging cells called nematocysts, however, the type of stinging cells
differs on these two parts of the body. This box jelly also has a primitive and transparent
eye on each side of its bell.
- Other Physical Features
- ectothermic
- radial symmetry
- polymorphic
- venomous
Development
Cubozoans have a two-stage life cycle consisting of a medusa and polyp. Fertilized
eggs develop into swimming planulae, which settle after a few days. The planulae develop
into motile feeding polyps, which produce other budding polyps. Polyps take a few
months to mature, then begin metamorphosis by resorbing tentacles. Four new tentacles
and four rhopalia are formed. When the single juvenile medusa has fully metamorphosed,
it contracts and swims away.
Reproduction
The mating system of the Irukandji jellyfish has yet to be recorded, but in some cubazoan
species the adults release both sperm and eggs into the ocean where fertilization
will occur.
Mature females of
Carukia barnesi
are defined as having fully developed oocytes. This typically occurs when the bell
height exceeds 8 mm. Males are considered mature when bell height is comparable to
that of mature females.
- Key Reproductive Features
- sexual
- fertilization
At this time there is no known parental care.
- Parental Investment
- no parental involvement
Lifespan/Longevity
At this time the lifespan of Carukia barnesi is not known.
Behavior
The Irukandji jellyfish has been found to be both fast and agile while swimming.
- Key Behaviors
- motile
Communication and Perception
Carukia barnesi
have image-forming eyes that respond to images, but have no brain to process the
visual information.
- Perception Channels
- visual
Food Habits
As
C. barnesi
matures, its diet switches from invertebrates to vertebrates. Box jellyfish in general
utilize a toxin to paralyze their prey. The toxin is injected into the prey by the
prey triggering one of the stinging cells (nematocysts) on the jellyfish’s tentacle.
Once the stinging cell is triggered, a harpoon looking coil is released which stings
the prey and the toxin then flows through this hollow harpoon into the prey. The tentacle
can then be retracted back into the jellyfish, bringing the prey with it towards the
jellyfish’s mouth, which is located inside the bell.
- Primary Diet
-
carnivore
- piscivore
- insectivore
- eats non-insect arthropods
- eats other marine invertebrates
- Animal Foods
- fish
- other marine invertebrates
Predation
Irukandji jellyfish are small and colorless, making them difficult to find.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
The role of Carukia barnesi in its ecosystem is currently not known.
Economic Importance for Humans: Positive
There is no known human benefit from this species except that it serves to be an interesting research specimen because of the symptoms it causes when a person is stung.
- Positive Impacts
- research and education
Economic Importance for Humans: Negative
Usually about 30 minutes after a person is stung by
C. barnesi
the victim begins to experience the following symptoms: a severe back or headache,
shooting pain throughout the muscles in their chest and abdomen, nausea, anxiety,
restlessness, and sometimes vomiting. Occasionally fluid may fill the lungs, which
if not treated could be fatal. These symptoms can last from hours to days and requires
hospitalization. No conclusive information has been obtained regarding the contents
of the venom, but it might contain a neurotoxin that is a neural Na+ channel activator.
No antivenom has yet been developed for this species.
- Negative Impacts
-
injures humans
- bites or stings
- venomous
Conservation Status
Carukia barnesi has not been given special conservation status.
Other Comments
Carukia barnesi
is in the Class Cubozoa, Order Carybdeida, and Family Carybdeidae.
Carukia barnesi
was named after Dr. Jack Barnes who was searching for the jellyfish who caused the
Irukandji syndrome. He had confirmed that the jellyfish he found did cause Irukandji
syndrome by stinging himself, his son, and a surf life saver, sending them all to
the hospital, in 1964. It was Hugo Flecker, however, that had named the overall syndrome
caused by this jellyfish, the Irukandji syndrome.
Additional Links
Contributors
Vishal Patel (author), Rutgers University, Selina Ruzi (author), Rutgers University, David V. Howe (editor), Rutgers University.
- Australian
-
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- saltwater or marine
-
mainly lives in oceans, seas, or other bodies of salt water.
- reef
-
structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.
- coastal
-
the nearshore aquatic habitats near a coast, or shoreline.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- radial symmetry
-
a form of body symmetry in which the parts of an animal are arranged concentrically around a central oral/aboral axis and more than one imaginary plane through this axis results in halves that are mirror-images of each other. Examples are cnidarians (Phylum Cnidaria, jellyfish, anemones, and corals).
- polymorphic
-
"many forms." A species is polymorphic if its individuals can be divided into two or more easily recognized groups, based on structure, color, or other similar characteristics. The term only applies when the distinct groups can be found in the same area; graded or clinal variation throughout the range of a species (e.g. a north-to-south decrease in size) is not polymorphism. Polymorphic characteristics may be inherited because the differences have a genetic basis, or they may be the result of environmental influences. We do not consider sexual differences (i.e. sexual dimorphism), seasonal changes (e.g. change in fur color), or age-related changes to be polymorphic. Polymorphism in a local population can be an adaptation to prevent density-dependent predation, where predators preferentially prey on the most common morph.
- venomous
-
an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- external fertilization
-
fertilization takes place outside the female's body
- motile
-
having the capacity to move from one place to another.
- visual
-
uses sight to communicate
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- venomous
-
an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).
- carnivore
-
an animal that mainly eats meat
- piscivore
-
an animal that mainly eats fish
- insectivore
-
An animal that eats mainly insects or spiders.
References
Barnett, F., D. Durrheim, R. Speare, R. Muller. 2005. Management of Irukandji syndrome in northern Australia. Rural and Remote Health , 5: 369. Accessed June 06, 2011 at http://www.rrh.org.au/articles/subviewnew.asp?ArticleID=369 .
Carrette, T., J. Seymour. 2002. "James Cook University Tropical Australian Stinger Research Unit" (On-line pdf). Accessed June 10, 2011 at http://www.jcu.edu.au/interest/stingers/irukandji%20brochure1.pdf .
Collins, A. 2000. "Cubozoa: Life history and ecology" (On-line). University of California Museum of Paleontology. Accessed June 11, 2011 at http://www.ucmp.berkeley.edu/cnidaria/cubozoalh.html .
Collins, A. 2009. Evolution of box jellyfish (Cnidaria: Cubozoa), a group of highly toxic invertebrates. Proceedings of the Royal Society , 277 (1680): 493-501. Accessed June 10, 2011 at http://rspb.royalsocietypublishing.org/content/277/1680/493.full .
Fenner, P. 2005. Dangerous Australian box jellyfish. South Pacific Underwater Medicine Society Journal , 35: 76-83. Accessed June 10, 2011 at http://gtuem.praesentiert-ihnen.de/tools/literaturdb/project2/pdf/SPU03088 .
Goggin, L. 2002. "Irukandji Jellyfish" (On-line). CRC Reef Research Centre. Accessed June 10, 2011 at http://www.reef.crc.org.au/discover/plantsanimals/irukandji/index.html .
Underwood, A., J. Seymour. 2007. Venom ontogeny, diet and morphology in Carukia barnesi , a species of Australian box jellyfish that causes Irukandji syndrome. Toxicon , 49 (8): 1073-1082. Accessed June 06, 2011 at http://www.sciencedirect.com/science/article/pii/S004101010700044X .
Winkel, K., G. Hawdon, P. Fenner, L. Gershwin, A. Collins, J. Tibballs. 2003. Jellyfish antivenoms: past, present, and future. Journal of Toxicology , 22: 115-127. Accessed June 10, 2011 at http://www.ecolevol.de/pubs/2003/Winkel-etal_JTox2003 .
Ávila-Soria, G. 2011. "Molecular characterization of Carukia barnesi and Malo kingi , Cnidaria; Cubozoa; Carybdeidae" (On-line pdf). Research online at JCU. Accessed December 11, 2010 at http://eprints.jcu.edu.au/8218/ .
Australian Medical Publishing Company. 1998. A year's experience of Irukandji envenomation in far north Queensland. The Medical Journal of Australia , 169: 638-641. Accessed June 10, 2011 at http://www.mja.com.au/public/issues/xmas98/little/little.html#footadd10 .
Getaway Guide. 2010. "Great Barrier Reef - Irukandji" (On-line). Barrier Reef Australia. Accessed June 10, 2011 at http://www.barrierreefaustralia.com/the-great-barrier-reef/irukandji.htm .
2009. "Irukandji syndrome" (On-line). Dr. Luciano Schiazza. Accessed June 10, 2011 at http://www.lucianoschiazza.it/Documenti%20new/Sindrome_irukandji_eng.html .