Periphylla periphylla

Model created for exhibition DEEP SEA CREATURES INTERACTIVE CATALOGUE

Ecological Education Centre - HYDROPOLIS

The scyphozoan helmet jellyfish (Periphylla periphylla) is a luminescent, red-colored jellyfish of the deep sea. They grow to 30 cm, and are found at depths of 700 m in every ocean of the world, as well as in the Norwegian fjords and in the Mediterranean Sea. As many other deep sea creatures, the helmet jellyfish is bioluminescent. Periphylla periphylla represents an exceptional life cycle, very rarely found in the phylum Cnidaria: the medusae do not go through a polyp stage, instead they strew fertilized eggs in open water and these develop directly into medusae, whose development rests entirely upon the egg's high yolk supply.

At night the helmet jellyfish leaves the depths and swims up in the water column to feed on plankton. With a full stomach it returns from the surface back to the depths when the sun rises.

Photos Rasmus Sigvaldi