The most recognized form of a jellyfish and a basic stage in its life cycle takes the name of what fearsome monster in mythology? (hint: stone!)
"always much greater than the Lion's Mane, whose bell diameter can reach . The rarely encountered deep-sea jellyfish ""Stygiomedusa gigantea"" is another candidate for ""largest jellyfish"", with its thick, massive bell up to wide, and four thick, ""strap-like"" oral arms extending up to in length, very different from the typical fine, threadlike tentacles that rim the umbrella of more-typical-looking jellyfish, including the Lion's Mane. Jellyfish have a complex life cycle which includes both sexual and asexual phases, with the medusa being the sexual stage in most instances. Sperm fertilize eggs, which develop into larval planulae, become polyps, bud into ephyrae"
"Amphipoda, regularly ride on its bell and even steal food from its oral arms and tentacles. The lifecycle of this jellyfish is well known, because it is kept in culture at the Monterey Bay Aquarium. It alternates between a benthic stage attached to rocks and piers that reproduces asexually and the planktonic stage that reproduces sexually in the water column; both males and females occur in the plankton. A smaller jellyfish, ""Cotylorhiza tuberculata"", typically found in warmer water, particularly in the Mediterranean Sea, is also popularly called a fried egg jellyfish. Phacellophora camtschatica Phacellophora camtschatica, commonly known as the fried"
"the organism. The specific representation of cnidae is referred to as the cnidome of that species and may represent a dynamic aspect of the cnidarian species that is responsive to prey availability or the developmental stage of the organism. Nematocysts are very efficient weapons. A single nematocyst has been shown to suffice in paralyzing a small arthropod (""Drosophila"" larva). The most deadly cnidocytes (to humans, at least) are found on the body of a box jellyfish. One member of this family, the sea wasp, ""Chironex fleckeri"", is ""claimed to be the most venomous marine animal known,"" according to the Australian"
"the word ""fish"" with its connotations of an animal with a backbone, though shellfish, cuttlefish and starfish are not vertebrates either. In scientific literature, ""jelly"" and ""jellyfish"" have been used interchangeably. Many sources refer to only scyphozoans as ""true jellyfish"". The term jellyfish broadly corresponds to medusae, that is, a life-cycle stage in the Medusozoa. The American evolutionary biologist Paulyn Cartwright gives the following general definition: The Merriam-Webster dictionary defines jellyfish as follows: Given that jellyfish is a common name, its mapping to biological groups is inexact. Some authorities have called the comb jellies and certain salps jellyfish, though other"
"from that of scyphozoans, and is used to catch prey (small fish and invertebrates, including prawns and bait fish) and for defence from predators, which include the butterfish, batfish, rabbitfish, crabs (blue swimmer crab) and various species of turtle including the hawksbill sea turtle and flatback sea turtle. It seems that sea turtles are unaffected by the stings because they seem to relish box jellyfish. Although the box jellyfish has been called ""the world's most venomous creature"", only a few species in the class have been confirmed to be involved in human deaths, and some species pose no serious threat"
"floating on the surface. When conditions returned to normal, the jellyfish disappeared. The long tentacles of ""Chiropsalmus quadrumanus"" are armed with nematocysts, the purpose of which is to capture prey such as small fish and to deter predators. They can inflict an extremely painful sting on people that encounter them. There is a documented case of a four-year-old boy in the Gulf of Mexico dying within forty minutes of being stung. Of forty-nine people stung by jellyfish off the coast of Brazil over a five-year period, twenty were by identifiable species. Sixteen of these were identified as being caused by"
"to be stung by the jellyfish, while his 14-year-old son and a lifeguard looked on. The jellyfish was later named after him. ""Carukia barnesi"" is a soft-bodied marine organism. This species falls within the Medusozoa subphylum and the Cubozoa class. It is a type of “Box Jellyfish” that is known for producing potent venom and is known for inflicting the Irukandji syndrome. Threat to Humans: The Irukandji syndrome was first discovered after a group of swimmers were stung in the open water near North Queensland, Australia. Victims of the sting reported severe symptoms of muscle aches, back pain, nausea, headaches,"
"Inimicus Inimicus is a genus of venomous fishes, closely related to the true stonefishes. This genus is a member of the family Synanceiidae (devilfishes, goblinfishes, and stonefishes) of the ray-finned fish order Scorpaeniformes. These benthic fishes are found on sandy or silty substrates of lagoon and seaward reefs, in coastal regions of tropical oceans. The ten described species are collectively known by various common names, including ghoul, goblinfish, sea goblin, spiny devilfish, stinger, and stingfish). The members of the genus ""Inimicus"" are nearly identical in appearance and behavior, and often confused with one another. There are currently 10 recognized species"
"making them the oldest multi-organ animal group. Jellyfish are eaten by humans in certain cultures, being considered a delicacy in some Asian countries, where species in the Rhizostomae order are pressed and salted to remove excess water. They are also used in research, where the green fluorescent protein, used by some species to cause bioluminescence, has been adapted as a fluorescent marker for genes inserted into other cells or organisms. The stinging cells used by jellyfish to subdue their prey can also injure humans. Many thousands of swimmers are stung every year, with effects ranging from mild discomfort to serious"
"hydroid stage of the lifecycle, a tiny sessile polyp called a scyphistoma. The scyphistoma reproduces asexually, producing similar polyps by budding, and then either transforming into a medusa, or budding several medusae off from its upper surface via a process called strobilation. The medusae are initially microscopic, and may take years to reach sexual maturity. Scyphozoa include the moon jelly ""Aurelia aurita"", in the order Semaeostomeae, and the enormous ""Nemopilema nomurai"", in the order Rhizostomeae, found between Japan and China and which in some years causes major fisheries disruptions. The jellyfish fished commercially for food are Scyphomedusae in the order"
"that include prey capture, defense, locomotion and attachment. When fully formed cnidae are called cnidocytes. When stimulated the cnidae secrete nematocyst toxins that are biological poisons. ""P. noctiluca"" is a member of the cnidarian class Scyphozoa and adapted to a pelagic mode of life. Whereas most scyphozoan jellyfish (also called scyphomedusae) have a complex life cycle with both the pelagic (swimming) jellyfish, or medusa, stage and a bottom-living polyp stage, ""Pelagia"" has adapted in such a way that the polyp stage appears absent, thus direct development exists. The male and female jellyfish spawn respectively sperm and eggs, which develop directly"
"to their natural habitat. The jellyfish is translucent, usually about in diameter, and can be recognized by its four horseshoe-shaped gonads, easily seen through the top of the bell. It feeds by collecting medusae, plankton, and mollusks with its tentacles, and bringing them into its body for digestion. It is capable of only limited motion, and drifts with the current, even when swimming. The genus ""Aurelia"" is found throughout most of the world's oceans, from the tropics to as far north as latitude 70°N and as far south as 40°S. The species ""Aurelia aurita"" is found along the eastern Atlantic"
"Synanceia verrucosa Synanceia verrucosa is a fish species known as the reef stonefish. It is a carnivorous ray-finned fish with venomous spines. It lives on reef bottoms camouflaged as a rock. It is the most venomous known fish in the world. It can be lethal to humans. This stonefish is usually brown or gray, and it may have areas of yellow, orange or red. This species reaches up to 30–40 centimeters long; a specimen of 51 centimeters has been recorded. This stonefish lives primarily above the Tropic of Capricorn. It is the most widespread species in the stonefish family, and"
"a jellyfish swimming by going to the surface and then slowly sinking with its arms spread evenly around its body; many octopus predators avoid jellyfish. Sole fish - This flat, poisonous fish is imitated by the mimic octopus by building up speed through jet propulsion as it draws all of its arms together into a leaf-shaped wedge as it undulates in the manner of a swimming flat fish. The mimic octopus of tropical Indo-Pacific are reputed to mimic up to 15 species of other local marine organisms. Mimicry of a local, abundant flounder was observed; nearly 500 episodes were analyzed."
"medicine) are all from this order and include members of the families Catostylidae, Lobonematidae, Rhizostomatidae and Stomolophidae. The jellyfish are typically dried and/or salted. In China, which was the first country documented to use jellyfish as food, this has been practiced at least since the year 300 CE, but they are also commonly consumed in Japan (the largest consumer of jellyfish today), Korea and southeast Asia. Several countries outside Asia have also started catching and exporting these in recent decades. , there were 92 recognized extant species in Rhizostomeae. These belong in the following families: Rhizostomae Rhizostomae or Rhizostomeae is"
"the Cambrian of the Marjum Formation in Utah, USA, c. 540 mya. The main feature of a true jellyfish is the umbrella-shaped bell. This is a hollow structure consisting of a mass of transparent jelly-like matter known as mesoglea, which forms the hydrostatic skeleton of the animal. 95% or more of the mesogloea (the tissue that functions as a hydro-static skeleton) consists of water, but it also contains collagen and other fibrous proteins, as well as wandering amoebocytes which can engulf debris and bacteria. The mesogloea is bordered by the epidermis on the outside and the gastrodermis on the inside."
"blue whale – has earned it the status of one of the longest known animals in the world. As coldwater species, these jellyfish cannot cope with warmer waters. The jellyfish are pelagic for most of their lives but tend to settle in shallow, sheltered bays towards the end of their one-year lifespan. In the open ocean, lion's mane jellyfish act as floating oases for certain species, such as shrimp, medusafish, butterfish, harvestfish, and juvenile prowfish, providing both a reliable source of food and protection from predators . Predators of the lion's mane jellyfish include seabirds, larger fish such as ocean"
"gonads, and have demonstrated far weaker toxicity in stinging researchers. The stingers (nematocysts) are in clumps, appearing as rings of small red dots around the bell and along the tentacles. The Irukandji's small size and transparent body make it very difficult to see in the water. Very little is known about the life cycle and venom of Irukandji jellyfish. This is partly because they are too small and fragile requiring special handling and containment. Their venom is very powerful. They were erroneously blamed for killing 5 tourists during a 3-month period in Australia. In fact, no evidence exists to suggest"
"neurotoxins secreted from glands at the base of their needle-like dorsal fin spines which stick up when disturbed or threatened. The vernacular name of the species, the stonefish, derives from its grey and mottled camouflage similar to the color of a stone. Swimmers may not notice them and inadvertently step on them, triggering a sting. When the stonefish is disturbed, it may inject an amount of venom proportional to the amount of pressure applied to it. A study published in 2018 reports that stonefish also have the ability to extend a sharp, specialized spine known as a ""lachrymal saber"" as"
"several countries; jellyfish caused a cascading blackout in the Philippines in 1999, as well as damaging the Diablo Canyon Power Plant in California in 2008. They can stop desalination plants and ships' engines. Jellyfish Jellyfish or sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are not mobile, being anchored to the seabed by stalks. The bell can pulsate to provide propulsion and highly efficient locomotion. The tentacles"
"Scyphozoa The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish (or ""true jellies""). It may include the extinct fossil group the Conulariida, whose affinities are uncertain and widely debated. The class name Scyphozoa comes from the Greek word ""skyphos"" (σκύφος), denoting a kind of drinking cup and alluding to the cup shape of the organism. Scyphozoans have existed from the earliest Cambrian to the present. Most species of Scyphozoa have two life history phases, including the planktonic medusa or jellyfish form, which is most evident in the warm summer months, and an"
"shore. Like other jellyfish, lion's manes are capable of both sexual reproduction in the medusa stage and asexual reproduction in the polyp stage. Lion's mane jellyfish have four different stages in their year-long lifespan: a larval stage, a polyp stage, an ephyrae stage, and the medusa stage. The female jellyfish carries its fertilized eggs in its tentacle, where the eggs grow into larva. When the larva are old enough, the female deposits them on a hard surface, where the larva soon grow into polyps. The polyps begin to reproduce asexually, creating stacks of small creatures called ephyrae. The individual ephyrae"
"angles, it bears a somewhat eerie resemblance to a human head or skull. Since it is virtually transparent, the creature is nearly impossible to see in its habitat, posing particular danger to swimmers. When the jellyfish are swimming, the tentacles contract so they are about 15 cm long and about 5 mm in diameter; when they are hunting, the tentacles are thinner and extend to about 3 m long. The tentacles are covered with a high concentration of stinging cells called cnidocytes, which are activated by pressure and a chemical trigger; they react to proteinous chemicals. Box jellyfish are day"
"Irukandji jellyfish Irukandji jellyfish ( ) are any of several similar, extremely venomous species of box jellyfish. With an adult size of roughly a cubic centimetre (1 cm), they are both the smallest and one of the most venomous jellyfish in the world. They inhabit the northern marine waters of Australia. They are able to fire their stingers into their victim, causing symptoms collectively known as Irukandji syndrome. There are about 16 known species of Irukandji, of which ""Carukia barnesi"", ""Malo kingi"", ""Malo maxima"", ""Malo filipina"" and ""Malo bella"" are the best-known. The symptoms of Irukandji syndrome were first documented"
"recommended treatment. Chironex fleckeri Chironex fleckeri, commonly known as the sea wasp, is a species of extremely venomous box jellyfish found in coastal waters from northern Australia and New Guinea north to the Philippines and Vietnam. It has been described as ""the most lethal jellyfish in the world"", with at least 63 known deaths in Australia from 1884 to 1996. Notorious for its sting, ""C. fleckeri"" has tentacles up to long covered with millions of cnidocytes which, on contact, release microscopic darts delivering an extremely powerful venom. Being stung commonly results in excruciating pain, and if the sting area is"
"from the environment. This symbiotic relationship is called mutualism, where ""both"" species benefit from their interactions. As a cnidarian, this jellyfish has an asexual and sexual reproduction. It reproduces by budding when it is in a polyp form. When it is in a medusa form, it reproduces sexually. The medusa female produces the eggs and keeps them. As the male produces the sperm and releases them in the water, the female uses its tentacles to bring the sperm to fertilize its eggs. This jellyfish can measure the maximum of 30.0 cm wide. The species can deliver a painful sting. Symptoms"
"disperse widely and is followed by a sedentary polyp phase. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoans (the ""true jellyfish"") are exclusively marine, but some hydrozoans with a similar appearance live in freshwater. Large, often colorful, jellyfish are common in coastal zones worldwide. The medusae of most species are fast growing, mature within a few months and die soon after breeding, but the polyp stage, attached to the seabed, may be much more long-lived. Jellyfish have been in existence for at least 500 million years, and possibly 700 million years or more,"
"jellyfish, because jellyfish feed on plankton, which includes fish eggs and larvae. Jellyfish form a component of jelly-falls, events where gelatinous zooplankton fall to the seafloor, providing food for the benthic organisms there. In temperate and subpolar regions, jelly-falls usually follow immediately after a bloom. Most jellyfish are marine animals, although a few hydromedusae inhabit freshwater. The best known freshwater example is the cosmopolitan hydrozoan jellyfish, ""Craspedacusta sowerbii"". It is less than an inch (2.5 cm) in diameter, colorless and does not sting. Some jellyfish populations have become restricted to coastal saltwater lakes, such as Jellyfish Lake in Palau. Jellyfish"
"a speed of between per minute. Like other species in its genus it has comparatively sophisticated eyes with lenses. With their help it can detect obstacles such as posts or a ship's rudder and avoid them. It often occurs in small groups. The sting is venomous to humans but some swimmers do not notice any painful sensation. In severe cases, the symptoms can be systemic, including pain at the sting site and elsewhere, paresthesia, hyperesthesia and skin lesions, and may take a few months to fully disappear. Although it is far less dangerous than some box jellyfish species from other"
"there are many short, club-shaped ones that bear disk-like ends. ""C. tuberculata"" are the most common jellyfish of their entire order in the Mediterranean Sea. They experience an annual life cycle marked by summer population blooms, which is likely an adaptive result of the strong seasonal changes in their Mediterranean environment. Their phases of development are quite similar to that of their other jellyfish counterparts. ""C. tuberculata""s four main stages of growth include the swimming larvae known as planulae, younger, sessile polyps called scyphistomae, the undeveloped young adult intermediates known as ephyrae, and the adult jellyfish forms, called medusas. In"
"Helmet jellyfish The helmet jellyfish (""Periphylla periphylla"") is a luminescent, red-colored jellyfish of the deep sea, belonging to the order Coronatae of the phylum Cnidaria. It is the only species in the monotypic genus ""Periphylla."" ""P. periphylla"" represents an exception, very rarely found in the phylum ""Cnidaria"": the medusae do not go through a polyp stage, thus presenting a ""holopelagic"" life cycle. The medusae strew fertilized eggs in open water and these develop directly into medusae, whose development rests entirely upon the egg's high yolk supply. The ephyra stage common among other jellyfish is not observed in ""P. periphylla"". The"
"Box jellyfish Box jellyfish (class Cubozoa) are cnidarian invertebrates distinguished by their cube-shaped medusae. Some species of box jellyfish produce extremely potent venom: ""Chironex fleckeri"", ""Carukia barnesi"" and ""Malo kingi"". Stings from these and a few other species in the class are extremely painful and can be fatal to humans. At least 51 species of box jellyfish were known as of 2018. These are grouped into two orders and eight families. A few new species have since been described, and it is likely that additional undescribed species remain. Class Cubozoa The medusa form of a box jellyfish has a squarish,"
"far have tentacles. It was named after the marine biologist John Keesing, who captured one near Shark Bay in 2013. This and another new species bring the total number of jellyfish known to cause Irukandji syndrome worldwide up to 16, four them coming from Western Australia. Keesingia Keesingia gigas, the ""giant"" (Greek ""gigas"") ""Keesingia"", is one of two new species of Irukandji jellyfish, the only one of the genus Keesingia in the Alatinid family. Found off the north-west coast of Western Australia, the species is able to deliver an extremely deadly sting which can cause the victim to experience the"