This particular species of jellyfish is found commonly in the Pacific Ocean from Australia to the Philippines. [Note: It is also found rarely in the Caribbean, but it is not common enough there to create serious hazards for swimmers.] (Bayer and Owre 1968)
This creature is found in abundance in the Indo-Pacific region and appears to travel towards the shores of mainlands in calm weather on a rising tide.
Sea wasps are pale blue and transparent so they are quite difficult to see because they are almost invisible in the clear ocean water. The jellyfish has a shape of a bell or a cube with four distinct sides, hence its local alias "box jellyfish". Each of the four corners along each side projects into pedaliums, each of which may contain as many as 15 tentacles reaching 3 meters in length individually. The outer ectoderm, or epidermis, contains the nematocysts, the stinging cells characteristic to the phylum. The inner endoderm, or gastrodermis, lines the gut. In between the epidermis and gastrodermis is the mesoglea, a layer of jelly-like substance which contains scattered cells and collagen fibers. The mouth is surrounded by a ring of stinging tentacles.
The reproduction of this jellyfish includes both sexual and asexual phases. The sexual phase requires for a female jelly to release eggs and for the male jelly to fertilize them. The fertilized eggs then become larva and eventually polyps. The polyps reproduce asexually by budding, a process in which young jellies grow on the polyp and are released to swim free and grow into adults. The sea wasp season in northern Australia starts with the onset of the wet season, which usually begins in October and ends in April. The sea wasp season in southern Australia is usually from November to March. They virtually disappear in the winter time from the Australian coasts.
Sea wasps are not aggressive and do not assertively hunt for food. They are very fast swimmers (reaching speeds of up to 5 mph), so fish are easily tangled in their tentacles while they are swimming. For mobility, it contracts with a jet-like motion, shooting itself about the water. It has eyes connected to a nerve ring so the creature can take action, if necessary, and swim towards its prey.
These creatures prey on small crustaceans and small fish. They congregate near the mouths of creeks and rivers following rain because it is thought that food is washed down these waterways towards the waiting jellyfish.
A considerable number of people are killed each year by these transparent, grapefruit-sized predators. Laboratory experiments have shown that the sea wasp's venom is 700 times more powerful than that of the better known Portuguese Man-of-War. Victims usually experience shock, muscular cramps, numbness, nausea, vomiting, severe backache, frothing at the mouth, constriction of the throat, loss of speech, difficulty in breathing, paralysis, delirium, convulsion, and ultimately, death. Once the venom from the sea wasp enters the human bloodstream, it can paralyze the heart in 30 seconds. The pain caused by the venom has been described as the most excruciating in the world. (Edmonds 1978)
Despite its deadly stinging cells, sea wasps do have predators that will hunt for them. Various turtles and sea slugs native to the Indo-Pacific region are not affected by their stinging cells. Some sea slugs even re-use the nematocysts for their own defenses!
Roy Rivera, Jr. (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
the nearshore aquatic habitats near a coast, or shoreline.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
the area in which the animal is naturally found, the region in which it is endemic.
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).
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.
Bayer, F., H. Owre. 1968. The Free-Living Lower Invertebrates. New York: Macmillan.
Calvin, J., J. Hedgpeth, E. Rickettes. 1985. Between Pacific Tides. Stanford: Stanford Press.
Edmonds, C. 1978. Dangerous Marine Animals of the Indo-Pacific Region. Newport: Wedneil Publications.
Grey, D. 1978. Sea Wasps (Scyphozoa: Cubomedusae) in the Northern Territory. Northern Territory Naturalist, Vol. 1: 1-+.
Stachowitsch, M. 1992. The Invertebrates. New York: Wiley-Liss, Inc..
Waggoner, B. August 30, 1995. "Introduction to the Cubozoans" (On-line). Accessed February 3, 2000 at http://www.ucmp.berkeley.edu/cnidaria/cubozoa.html.