This massive jellyfish lives in the cold waters of the Arctic, northern Atlantic, and northern Pacific oceans. It has a very unique muscular system. The perirhopalial tissue is basically the swimming muscle of Cyanea. The perirhopalial tissue is a thin, triangular septum found below the umbrella surface of the animal. It separates part of the gastric canal system from the surrounding seawater, and is bound on two sides by radial muscle bands and on the third, the shorter side, by a rhopalium and the margin of the bell.
The swimming muscle is striated and composed of myoepithelial cells. Each myoepithelial cell has several muscle tails, and those of adjacent cells are linked together by desmosomes.
It is important to note that these jellyfish are composed mainly of smooth muscles.