Thimble jellyfish Thimble jellyfish The thimble jellyfish ("Linuche unguiculata") is a species of cnidarian found in the neotropical Atlantic Ocean. It is a tiny jellyfish with a straight-sided, flat-topped bell. This jellyfish is the most common cause of seabather's eruption, a reaction caused by the injection of juvenile jellyfish nematocysts into human skin. The medusa of the thimble jellyfish has straight sides with sixteen grooves, and a flat top. The coronal groove between the top and sides provides flexibility. The margin of the bell has sixteen lappets (folds), the niches between these bearing alternately rhopalia (sense organs) and short tentacles (eight of
Cannonball jellyfish Such complications are associated also with toxins of other cnidaria. The toxin is also harmful to the eyes; contact with a nematocyst can be very painful, followed by redness and swelling. However, cannonball jellyfish are mostly harmless to humans. Contact with them may cause the skin to itch slightly, or minor eye irritation. One of the main predators of cannonball jellyfish is the endangered species leatherback sea turtle. Cannonball jellyfish are also commercially harvested as food for humans. Along the coast of the southern U.S. state of Georgia, jellyfish are a valuable export, which end up on dining tables across