Harmless

Cotylorhiza tuberculata

Scyphozoa (Cepheidae)

It lives in symbiosis with micro-algae (zooxanthellae) hosted in its tissues. These algae give it its beautiful colors and help it feed through sunlight.

Sting symptoms

Completely harmless. Does not sting.

Identification

It literally looks like a fried egg: the center is domed, smooth, and yellow-orange, surrounded by a lighter flat disk. Underneath, its short oral arms end in bright purple or blue buttons.