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Jellyfish are composed of 94% water and are radially symmetrical. It is dibloblastic, which means that it has two tissue layers. This member of the giant jellyfish has a hemispherical bell with scalloped edges. The bell is divided into eight obvious lobes by eight indentations with second order indentations. Some lobes contain sense organs including odor pits, balance organs, and simple light receptors. Its bell normally ranges in diameter from 30 to 80 cm, with some individuals growing up to a maximum of 180 cm. The oral arms are purple with reddish or yellow tentacles, hence the common name "Lion's Mane". The bell may be pink to reddish-gold or brownish-violet. The jellyfish has no fringing tentacles around the edge of its bell, but it has eight groups of 150 tentacles each on the underside of its umbrella. These tentacles contain very effective nematocysts, as does the upper surface of the jellyfish. (Banister and Campbell 1985, Grzimek 1972, Nichols 1979, Stachowitsch 1992)
Other Physical Features: ectothermic ; radial symmetry
The Lion's Mane Jellyfish is found in the cooler regions of the Atlantic, Pacific, North Sea, and Baltic Sea. They are especially common along the East coast of Britain. They are found in the pelagic zone as medusae and then benthic zone as polyps. (Grzimek 1972, Nichols 1979)
Aquatic Biomes: benthic
Cyanea capillata can be found in the cooler regions of the Atlantic, Pacific, North Sea and Baltic. They are especially prevalent near the east coast of Britain. (Grzimek 1972, Nichols 1979)
Biogeographic Regions: atlantic ocean (Native ); pacific ocean (Native )
Cyanea capillata feeds mainly on fish. It catches its prey by sinking slowly with its tentacles spread in a circle around it. The prey is captured in the "net" of tentacles and stunned by the nematocysts. (Grzimek 1972)
Cyanea capillata is in no danger of extinction.
US Federal List: no special status
One of the most distingulishing features of Cyanea capillata is its coloration. Its tendency to form shoals is also fairly unusual. The extremely effective nematocysts are also a prominent feature. Even a dead animal or a detached tentacle is capable of stinging. (Grzimek 1972)
The medusa form of the jellyfish reproduces sexually and has separate sexes. The ova and sperm are produced in baglike projections of the stomach wall. The sex cells are relased through the mouth for external fertilization. In the case of Cyanea, the eggs are held in the oral tentacles until the planula larvae develop. The planula larvae then settle on the substrate and develop into polyps. These scyphopolyps reproduce asexually by horizontal division (strobilation) and are then termed strobila. With each division, a small disk forms, and when multiple disks have formed, the uppermost one detaches and swims off as a ephyra. The ephyra develops into the recognized medusa form of the jellyfish. (Grzimek 1972)
Parental Investment: no parental involvement
The lion's mane jellyfish is one of the largest species of jellyfish. One specimen that was found was 2.3 m in diameter and its tentacles were 36.5 m in length (Lion's mane jellyfish). There are as many as 150 long tentacles that are present beneath each of the eight lobes (Lion's mane jellyfish- Cyanea capillata).
Arctic, northern European, North American Atlantic and Pacific, southern Australian, and waters (Lion's mane jellyfish- Cyanea capillata).
This type of jellyfish is a coldwater species, it cannot cope in warm water (Lion's mane jellyfish). The medusae prefer cool temperatures below 70 degrees.
"They possess a benthic polyp stage (larva) which reproduces asexually to give rise to ephyrae; these grow into dioecious, planktonic medusae (adults) that produce planulae (motile stereogastrulae), and the latter settle to the benthos to form polyps, completing the cycle "(Brewer).
Cyanea capillata can sexually reproduce during the medusa stage and can asexually reproduce during the polyp stage (Lion's mane jellyfish).
Feeds on zooplankton, small fish, ctenophores, and moon jellies (Lion's mane jellyfish). Their long tentacles capture large prey and bring them into their oral arms, where they are then enveloped and digested (Lion's mane jellyfish- Cyanea capillata).
Coloration bright and varied, most often of red or yellow tint.
Cold-water species
Small fish larvae often find shelter beneath the umbrella.
The edge of the umbrella carries 16 large lobes and 8 rhopalia. Feeding tentacles have numerous folds. 8 groups of long tentacles originate from the subumbrella surface near the edge of the umbrella. Radial and circular musculature very well developed.
One of the largest scyphomedusae, diameter of the umbrella may reach 2 m, the length of the tentacles 20-30 m.
The lion's mane jellyfish (Cyanea capillata), also known as the giant jellyfish, arctic red jellyfish, or the hair jelly,[2] is one of the largest known species of jellyfish. Its range is confined to cold, boreal waters of the Arctic, northern Atlantic, and northern Pacific Oceans. It is common in the English Channel, Irish Sea, North Sea, and in western Scandinavian waters south to Kattegat and Øresund. It may also drift into the southwestern part of the Baltic Sea (where it cannot breed due to the low salinity). Similar jellyfish – which may be the same species – are known to inhabit seas near Australia and New Zealand. The largest recorded specimen was measured off the coast of Massachusetts in 1865 and had a bell with a diameter of 210 centimetres (7 feet) and tentacles around 36.6 m (120 ft) long.[3] Lion's mane jellyfish have been observed below 42°N latitude for some time in the larger bays of the East Coast of the United States.
The lion's mane jellyfish uses its stinging tentacles to capture, pull in, and eat prey such as fish, zooplankton, sea creatures, and smaller jellyfish.[4]
The taxonomy of the Cyanea species is not fully agreed upon; some zoologists have suggested that all species within the genus should be treated as one. Two distinct taxa, however, occur together in at least the eastern North Atlantic, with the blue jellyfish (Cyanea lamarckii Péron & Lesueur, 1810) differing in color (blue, not red) and smaller size (10–20 cm [3+7⁄8–7+7⁄8 inches] diameter, rarely 35 cm [14 inches]). Populations in the western Pacific around Japan are sometimes distinguished as Cyanea nozakii, or as a subspecies, C. c. nozakii. In 2015, Russian researchers announced a possible sister species, Cyanea tzetlinii found in the White Sea, but this has not yet been recognized by other authoritative databases such as WoRMS or ITIS.[5]
Lion's mane jellyfish (Cyanea capillata) are named for their showy, trailing tentacles reminiscent of a lion's mane. They can vary greatly in size: although capable of attaining a bell diameter of over 2 m (6 ft 7 in), those found in lower latitudes are much smaller than their far northern counterparts, with a bell about 50 cm (20 in) in diameter. Larger specimens are typically further offshore than smaller ones. Juveniles are lighter orange or tan, very young lion's manes are occasionally colorless and adults are red and start to darken as they age.
While most jellyfish such as the moon jelly have a circular bell, the bell of the Lion's Mane is divided into eight lobes, resembling an eight-pointed star. Each lobe contains about 70 to 150 tentacles,[6][7] arranged in four fairly distinct rows. Along the bell margin is a balance organ at each of the eight indentations between the lobes – the rhopalium – which helps the jellyfish orient itself. From the central mouth extend broad frilly oral arms with many stinging cells called Cnidocytes.[8] Closer to its mouth, its total number of tentacles is around 1,200.[9]
The long, thin tentacles which emanate from the bell's subumbrella have been characterised as “extremely sticky”; they also have stinging cells. The tentacles of larger specimens may trail as long as 30 m (100 ft) or more, with the tentacles of the longest known specimen measured at 36.6 m (120 ft) in length, although it has been suggested that this specimen may actually have belonged to a different Cyanea species.[10] This unusual length – longer than a blue whale – has earned it the status of one of the longest known animals in the world.[11]
Lion's mane jellyfish remain mostly very near the surface, at no more than 20 m (66 ft) depth. Their slow pulsations weakly drive them forward, so they depend on ocean currents to travel great distances. The jellyfish are most often spotted during the late summer and autumn, when they have grown to a large size and the currents begin to sweep them to shore. Unlike most pelagic jellyfish, they are completely solitary and rarely travel in groups.
Like other jellyfish, lion's manes are capable of both sexual reproduction in the medusa stage and asexual reproduction in the polyp stage.[12] 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.[12] The female jellyfish carries its fertilized eggs in its tentacle, where the eggs grow into larvae. When the larvae are old enough, the female deposits them on a hard surface, where the larvae soon grow into polyps. The polyps begin to reproduce asexually, creating stacks of small, immature medusae called ephyrae.[13] The individual ephyrae break off from the stacks, where they eventually grow into the mature medusa stage to become full-grown jellyfish.[14]
Human encounters with the jellyfish can cause temporary pain and localized redness.[15] In normal circumstances, however, and in healthy individuals, the stings of the jellyfish are not known to be fatal; vinegar can be used to deactivate the nematocysts. If there is contact with a large number of tentacles, however, medical attention is recommended after exposure.
There may be a significant difference between touching a few tentacles with fingertips at a beach and accidentally swimming into the jellyfish. The initial sensation is more strange than painful and feels like swimming into warmer and somewhat effervescent water. Some minor pain will soon follow. Normally, there is no real danger to humans (with the exception of people suffering from special allergies). But in cases when someone has been stung over large parts of their body by not just the longest tentacles but the entire jellyfish (including the inner tentacles, of which there are around 1,200[9]), medical attention is recommended as systemic effects can be present.[16] Although rarely, severe stings in deep water can also cause panic followed by drowning.[17][9]
On a July day in 2010, around 150 beachgoers were stung by broken-up Lion's mane jellyfish remains in Wallis Sands State Beach, Rye, New Hampshire, USA. Considering the size of the species, it is possible that this incident was caused by a single specimen.[18]
The lion's mane jellyfish appears in the Sherlock Holmes short story "The Adventure of the Lion's Mane" published in The Case-Book of Sherlock Holmes. Holmes discovers at the end of the story that the true killer of a professor who died shortly after going swimming (shouting "the lion's mane" before he succumbed) was actually this jellyfish. Suspicion was originally laid upon the professor's rival in love, until the latter was similarly attacked (he survived, although badly stung). In the context of the story, it is only because the school professor has a weak heart that he succumbs, as is confirmed by the survival of the second victim.
A photograph widely distributed on the internet appears to show an anomalously large lion's mane dwarfing a nearby diver by several times. The photo was subsequently shown to be a hoax.[19]
On the popular television program QI, the show claimed that the longest animal in the world was the lion's mane jellyfish. This was later corrected – in 1864, a bootlace worm (Lineus longissimus) was found washed up on the coast of Fife, Great Britain, that was 55 m (180 feet) long. This claim is, however, disputed because bootlace worms can easily stretch to several times their natural length, so it is possible the worm did not actually grow to be that length. If that is the case, the lion's mane jellyfish would indeed be the longest animal in the world. [20]
Seabirds, larger fish such as ocean sunfish, other jellyfish species, and most sea turtles will only attack juveniles or smaller specimens while a fully grown adult is incapable of being eaten, due to their massive size and the abundance of stinging tentacles they possess, although both adults and juveniles have been documented eaten by anemones.[12] The leatherback sea turtle feeds almost exclusively on them in large quantities during the summer season around Eastern Canada.[21]
Lion's mane jellyfish, expanded
Lion's mane jellyfish capturing three moon jellyfishes
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Lion's mane jellyfish with full threads visible
Lion's mane jellyfish contracted
Lion's mane jellyfish in star formation
Lion's mane jellyfish open, showing underside
Life-sized model in the Smithsonian Museum of Natural History, Washington DC, US
Small, dead lion's mane jelly washing up on the beach
The lion's mane jellyfish (Cyanea capillata), also known as the giant jellyfish, arctic red jellyfish, or the hair jelly, is one of the largest known species of jellyfish. Its range is confined to cold, boreal waters of the Arctic, northern Atlantic, and northern Pacific Oceans. It is common in the English Channel, Irish Sea, North Sea, and in western Scandinavian waters south to Kattegat and Øresund. It may also drift into the southwestern part of the Baltic Sea (where it cannot breed due to the low salinity). Similar jellyfish – which may be the same species – are known to inhabit seas near Australia and New Zealand. The largest recorded specimen was measured off the coast of Massachusetts in 1865 and had a bell with a diameter of 210 centimetres (7 feet) and tentacles around 36.6 m (120 ft) long. Lion's mane jellyfish have been observed below 42°N latitude for some time in the larger bays of the East Coast of the United States.
The lion's mane jellyfish uses its stinging tentacles to capture, pull in, and eat prey such as fish, zooplankton, sea creatures, and smaller jellyfish.
