Jellyfish are graceful and complex creatures, that fascinate us with their pulsating movements and often colorful, translucent bodies. The Moon Jelly (Aurelia aurita) is a “true” jellyfish in the Class Scyphozoa (Phylum Cnidaria) and is a free-swimming medusa. The translucent bluish dome is conspicuous, as are the four, clover-leaf-shaped reproductive organs. As tempting as it is to touch, the numerous swaying thread-like tentacles have stinging cells or nematocysts, draping down from the dome, typical of cnidarians.
Sometimes tiny fish can be observed, skillfully darting around under the dome of the Moon Jelly. This is a form of symbiosis. These clusters of juvenile jacks gain protection from predators in the open water, as they find safety within the jellyfish’s tentacles.