Blue jellyfish in Brofjorden at Sandvik 15

Blue jellyfish in Brofjorden at Sandvik 25

''Cyanea lamarckii'', also known as the blue jellyfish or bluefire jellyfish, is a species of jellyfish in the family

Cyaneidae The Cyaneidae are a family of true jellyfish. About 20 species are in this family, including the well-known lion's-mane jellyfish. Species The following species are recognized within the family Cyaneidae. Formerly, this family also included th ...

Description

Blue jellyfish age can be identified by color of their bell. They tend to be pale in appearance when young, but mature to have a brightly purple-blue (some yellow) colored bell. Although it is similar to the lion's mane jellyfish, the blue jellyfish is not as large, and has a translucent bell. ''C. lamarckii'' has a blue or yellow tone and grows to approximately across, but specimens can grow to . In

Scandinavia Scandinavia; Sámi languages: /. ( ) is a subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, Norway, and S ...

n seas, this species rarely grows larger than . These jellyfish drift closer to the shore to catch the large abundance of plankton with their tentacles. This jellyfish has many stinging tentacles. The four mouth arms are large with many wrinkles and ripples. The jellyfish live off a diet of

phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. ...

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

as well as the eggs and larvae of other aquatic animals such as fish. ''Cyanea lamarkii'' use their tentacles containing

nematocysts A cnidocyte (also known as a cnidoblast or nematocyte) is an explosive cell containing one large secretory organelle called a cnidocyst (also known as a cnida () or nematocyst) that can deliver a sting to other organisms. The presence of this ce ...

to not only catch their prey, but to protect from predators.

Distribution

This species is found in the

pelagic zone The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or wa ...

off the west coast of

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to ...

, the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...

, the

English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" ( Cotentinais) or ( Jèrriais), ( Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Ka ...

, and the

Irish Sea The Irish Sea or , gv, Y Keayn Yernagh, sco, Erse Sie, gd, Muir Èireann , Ulster-Scots: ''Airish Sea'', cy, Môr Iwerddon . is an extensive body of water that separates the islands of Ireland and Great Britain. It is linked to the C ...

, sometimes with the more common lion's mane jellyfish (''Cyanea capillata'').

Taxonomy

The

taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

of ''Cyanea''

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

is not fully agreed upon. Some zoologists have suggested that all species within the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

should be treated as one. However, ''Cyanea lamarckii'' exists with two other distinct taxa in at least the eastern

North Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe a ...

. The species specifier originates from the French naturalist

Lamarck Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (; ), was a French naturalist, biologist, academic, and soldier. He was an early proponent of the idea that biolo ...

(Latin name form: Lamarckius).

Life cycle

The medusae bud and loosen from the mature polyps between January and March around the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isl ...

and southern North Sea. This occurs in a similar way to the life cycle of the

moon jellyfish ''Aurelia aurita'' (also called the common jellyfish, moon jellyfish, moon jelly or saucer jelly) is a species of the genus '' Aurelia''. All species in the genus are very similar, and it is difficult to identify ''Aurelia'' medusae without genet ...

. These blue jellyfish live for less than a year.

Description

Distribution

Taxonomy

Life cycle

References

Further reading