Lion’s mane jellyfish is one of the largest jellyfish. It rarely measures over 35 cm in diameter but the species has a several meters long veil consisting of almost invisible treads with poisoning nettle-cells. The jellyfish is often near the surface where it can get in touch with bathers. The treads are often stuck on an anchor rope.
When in contact with bathers the nettle-cells releases a small barbed poison needle that sprays a paralyzing poison into the skin. It stings badly in the skin and a burn can in worst-case trigger muscle cramps.