Cannonball Jellyfish

Description:

Its common name derives from its similarity to a cannonball in shape and size. Its dome-shaped bell can reach 25 cm (10 inches) in diameter and the rim is sometimes colored with brown pigment. Underneath of the body is a cluster of oral arms that extend out around the mouth. These arms function as a way of propulsion and aid in catching prey.

Habitat:

Cannonballs are prominent from North America's eastern seaboard all the way to Brazil, but are also found in parts of the Pacific. Cannonballs live in warm, estuarian waters, with an average temperature of 23.1 °C (73.6 °F) and average salinities of 33.8 ppt (parts per thousand). This one was observed at the beach at Huntington Beach State Park near Murrells Inlet, SC.

Notes:

Cannonballs eat mainly zooplankton such as veligers, and also all forms of red drum larvae. When disrupted the cannonball secretes a mucus out of its nematocyst that contains a toxin. The toxin harms small fish in the immediate area, and drives away most predators, except for certain types of crabs. Although cannonballs do not commonly sting humans, it still has toxins which can cause cardiac problems in animals and humans. The toxin causes irregular heart rhythms and problems in the myocardial conduction pathways. Such complications are associated also with toxins of other coelenterates. The toxin is also harmful to the eyes, when the nematocyst comes in contact with eyes it is very painful and is followed with redness and swelling.