Harmless

Rhizostoma octopus

Scyphozoa (Rhizostomatidae)

One of the largest jellyfish in Europe. Despite its impressive size, it often shelters small juvenile fish that come to hide under its umbrella to protect themselves from predators.

Sting symptoms

Generally harmless, but the mucus released in the water around it can be slightly irritating.

Identification

Massive, white to bluish bell-shaped, often with a blue or purple edge. It has no long tentacles but very large, folded oral arms resembling a cauliflower.