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.