Cyanea lamarckii

Maximun diametre: 30 cm, but in scandinavian waters rarely larger than 15 cm.

Appearance: Blue or yellow tone. It has a great many stinging tentacles that hang from the underside of the jellyfish. The four mouth arms, also hanging from the underside, are large and have many wrinkles and ripples.
Compare the Cyanea lamarckii with the lion´s mane, moon och rhizostome jellyfish.

Depth: Sea-surface to unknown depth.

Environment: Pelagic.

Misc: The medusae bud and loosen from the mature polyps in much the same way as in the lifecycle of the moon jellyfish. This occurs between January and March around the British Isles and southern North Sea. It is probably from these areas that the species has drifted when seen in other areas between the Bay of Biscay to Iceland. In scandinavian waters a minor number are seen between May and September.

Classification: Cyanea lamarckii is a member of the jellyfish group under the cnidarians.

Anthomedusae

Maximum height: 4 ,5 cm.

Appearance: The mouth is situated at the top of the tubular formationen that hangs from the middle of the "umbrella´s" underside. Along the inside edge is a peripheral crease, and the tantacles hang from the outer edge of the "umbrella". The anthomedusae tentacles are few, and the "umbrella" form is relatively high. The organs that produce eggs and sperms are placed by the mouth or on the stomach. The anthomedusae are usually transparent, although the nether parts of the mouth and the thicker areas of the tentacles are distinctly pigmented - black, brown, blue, red, yellow, green or other colour tones.
Compare the anthomedusae with the leptomedusae and other jellyfish.

Depth: Sea-level to unknown depth.

Environment: Pelagic.

Misc: The anthomedusae catches and eats small organisms and suspended remains from the surrounding water. These medusae do not sting enough to cause discomfort to people. Representatives of the anthomedusae group are found globally. The medusae stage is part of a life cycle that is similar to the leptomedusae.

Classification: The specimen in the picture above is probably of the species Neoturris pileata. Anthomedusae are part of the hydroid group under the cnidarians.

Compass jellyfish

Maximum diametre: approx. 20 cm.

Appearance: The compass jellyfish has a yellow-whitish colour with characteristic brown V-shaped lines on top of the "umbrella". The relatively large tentacles are few (24), and the four mouth arms are wrinkled and noticiably long.
Compare the compass jellyfish with the lion´s mane jellyfish.

Depth: From sea-level to unkown depth.

Environment: Pelagic.

Misc: Compass jellyfish change sex: first they are male, followed after by female. The medusae live mainly off other medusae, comb jellyfish and arrow worms. This species is a rarity in scandinavian waters, but medusae occasionally drift into nordic waters from the south during the summer and autumn.

Classification: The compass jellyfish is part of the jellyfish group under the cnidarians.

Comb jelly - Bolinopsis infundibulum

Maximum length: 15 cm.

Appearance: The jelly in Bolinopsis infundibulum is completely transparent, except with some adults that can have a milkish white colour. On the exterior of the oblong body, four long and four short comb-rows are situated. These can shimmer with the colours of the rainbow. Bolinopsis infundibulum has two small tentacles that are transformed into fringes along the sides of the creature. The mouth is surrounded by two flaps; while the other end of the body is drawn out into a obtuse point. Compare with the sea-gooseberry and other comb-jellies.

Depth: From the surface to unknown depth.

Environment: Pelagic.

Misc: Bolinopsis infundibulum is very fragile and almost always breaks when handled. On the two large flaps small organisms fasten and thereafter are transported to the mouth with the small flickering hairs. Certain fish, e.g. lump suckers and other comb-jellies feed on Bolinopsis infundibulum. Individual adults produce both eggs and sperm which they release into the water where fertilization takes place. It is possible to see Bolinopsis infundibulum shine in the dark.

Classification: Bolinopsis infundibulum is a member of the comb jelly group (ctenophora).

Leptomedusae

Maximum diameter: About 20 cm, but on exceptional occasions up to 30 cm.

Appearance: The mouth is situated at the top of the tubular formation that hangs down from the underside of the "umbrella". Along the inside edge of the "umbrella" is a peripheral crease and the tentacles hang down from the "umbrellas" outer edge. The leptomedusae have many tentacles, the number of which increase with age. The "umbrella" form is rather shallow, and on the underside, the organs that produce eggs and sperms are situated. The leptomedusae are usually transparent, but on occasions can be milky white or have a light blue, brown, red or violet tone. Even with transparent medusae, the sexual organs, stomach and tentacles can be light red, greenish or light brown.
Compare the leptomedusae with the anthomedusae and the moon jellyfish.

Depth: From sea-level to unknown depth.

Environment: Pelagic.

Misc: The leptomedusae catches and eats small organisms and suspended remains from the surrounding water. These medusae do not sting enough to cause discomfort to people. Medusae representatives are found globally. The medusa stage is part of a life cycle where even an attached stage is present and the medusae build colonies.

Classification: The above photo shows a jellyfish (Tima bairdii). Leptomedusae are part of the hydroid, group under the cnidarians.

Rhizostome jellyfish

Maximum diametre:About 50 cm, but on rare occasions up to 90 cm.

Appearance: The top of the "umbrella" has a blueish colour, while down on the outer edge small round pockets with a dark blue to violet colour. The males sexual organs are blue, while the females are yellow, brown or red. The medusae have no tentacles. The mouth arms have grown together and have about the same length as the diametre of the "umbrella". The whole of the body has a relatively solid consistency.
Compare the rhizostome jellyfish with the lion´s mane jellyfish and the cyanea lamarckii.

Depth: From sea-level to unknown depth.

Environment: Pelagic.

Misc: Rhizostome jellyfish can swim relatively quickly. The mouth arms have an extensive system of canals. Through these water is pumped and particles of food filtered out. There are stinging cells on the "umbrella", but are so weak that they hardly irritate human skin.
This species is rare in scandinavian waters, but medusae have drifted into nordic waters during the late summer and autumn.
Rhizostome jellyfish have in certain European areas been used as a food source for people.

Classification: The rhizostome jellyfish is a member of the jellyfish group under the cnidarians.

Lion´s mane jellyfish

Maximum diameter: 50 cm, but in Arctic waters har examples of about 2 m been observed.
Appearance: The Lion´s mane jellyfish has pronounced red or yellow colour. It has great number of long irritating stinging tentacles, that hang down from the underside of the "umbrella". The four mouth arms, that also hang from the "umbrellas" underside, are large with many wrinkles and creases.
Compare the lion´s mane jellyfish with cyanea palmstruchi, the compass jellyfish and rhizostoma octopus.

Depth: From sea-level to unkown depth.

Enviroment: Pelagic.

Övrigt: Contrary to the moon jellyfish´s lifecycle only one ephyra-larvae buds from each polyp, and this happens mainly during the spring.
Examples of the lion´s mane jellyfish have been seen as far as the Gulf of Finland.

Classification: The lion´s mane jellyfish is part of the group jellyfish, part of the group cnidaria.

Moon jellyfish

Maximum diametre: 25 cm, but on rare occassions can measure up to 40 cm.

Appearance:Moon jellyfish are easy to recognize because of their four reproductive organs that are round or horseshoe-shaped. Along the periphery of the slightly arched "umbrella", short tentacles are attached. On the underside, four mouth arms are present. From the middle of the jellyfish, four channels run outwardly to a peripheral channel that circumferences the jellyfish. The moon jellyfish is transparent with a slightly blueish or pinkish tone. Its genitals, mouth arms, tentacles and channels have a slightly white, violet, red or yellow tone. Compare the moon jellyfish with the leptomedusae and the cyanea lamarckii.

Depth: From sea-level to unkown depth.

Environment:Pelagic.

Classification: Moon jellyfish are members of the jellyfish group under the cnidarians.

Seasparkle

Maximum diameter: Approx. 2 mm, but seldom more than 1 mm in Scandinavian waters. Compare the size with a hair.

Appearance: Seasparkle is almost completely colourless and transparent, but when driven together in large numbers the water can appear thick and have a light brown to pink colour. The cell is relatively large and round and is furnished with three protrusions. Two of the protrusions are small and vague and can easily be believed to correspond to the mobile cell outgrowths on other dinoflagellates. The third protrusion, that is unique for seasparkle and known as a tentacle, is striped and much more pronounced than the others. All the protrusions are situated in a large deep groove on the underside of the cell.
In the picture above, the picture at the top depicts seasparkle from its underside, the left-hand picture depicts the right side of seasparkle, while the right-hand picture depicts it from above.
Depth: Seasparkle is most common in the upper reaches of the sea that recieves sunlight.

Environment: Pelagic.

Misc: Seasparkle is so large because it pumps itself up with water. By regulating the amount of ions it can effect its bouyancy and towards the end of the bloom they usually congregate at the surface. In the large cells, thousands of small reproductive bodies can be formed.
With the help of its tentacle seasparkle collects its food, which can be of the same size as itself, and carry it to its mouth which is situated at the bottom of the groove. Coloured particles seen in the cell are often particles of food or small photosynthesizing organisms that live together with the seasparkle.
Seasparkle is one of those organisms that cause phosphorescence of the sea in our waters!

Classification: Sea sparkle belongs to the dinoflagellate group under the "protists". The protists as a systematic group is not well motivated or defined, as it is used to collect organismer that are not bacterias, fungi, plants or animals into a common group.

Box Jellyfish Profile

The infamous box jellyfish developed its frighteningly powerful venom to instantly stun or kill prey, like fish and shrimp, so their struggle to escape wouldn’t damage its delicate tentacles.

Their venom is considered to be among the most deadly in the world, containing toxins that attack the heart, nervous system, and skin cells. It is so overpoweringly painful, human victims have been known to go into shock and drown or die of heart failure before even reaching shore. Survivors can experience considerable pain for weeks and often have significant scarring where the tentacles made contact.

Box jellies, also called sea wasps and marine stingers, live primarily in coastal waters off Northern Australia and throughout the Indo-Pacific. They are pale blue and transparent in color and get their name from the cube-like shape of their bell. Up to 15 tentacles grow from each corner of the bell and can reach 10 feet (3 meters) in length. Each tentacle has about 5,000 stinging cells, which are triggered not by touch but by the presence of a chemical on the outer layer of its prey.

Box jellies are highly advanced among jellyfish. They have developed the ability to move rather than just drift, jetting at up to four knots through the water. They also have eyes grouped in clusters of six on the four sides of their bell. Each cluster includes a pair of eyes with a sophisticated lens, retina, iris and cornea, although without a central nervous system, scientists aren’t sure how they process what they see.