Giant jellyfish, Arctic red jellyfish, Hair jelly
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.
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. The photo was subsequently shown to be a hoax.
On the 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.
Ca
CarnivoreA carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
Co
CosmopolitanAnimals with cosmopolitan distribution are those whose range extends across all or most of the world in appropriate habitats. Another aspect of cos...
Ov
OviparousOviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
L
starts withLion'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, 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. Closer to its mouth, its total number of tentacles is around 1,200.
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. This unusual length – longer than a blue whale – has earned it the status of one of the longest known animals in the world.
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. 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 a 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. The individual ephyrae break off from the stacks, where they eventually grow into the mature medusa stage to become full-grown jellyfish.
