Cassiopea

Cassiopea (upside-down jellyfish) is a genus of true jellyfish in the family Cassiopeidae. They are found in warmer coastal regions around the world, including shallow mangrove swamps, mudflats, canals, shallow lagoons and bays, and turtle grass flats in Florida, the Caribbean, Hawaii, the Red Sea, the Mediterranean Sea, and Micronesia. The medusa usually lives upside-down on the sea floor in shallow areas, which has earned them their common name. They have a symbiotic relationship with photosynthetic dinoflagellates and therefore must lie upside-down in areas with sufficient light.