Rhopalia

Rhopalia (singular rhopalium) are the most obvious sensory structures of scyphozoan jellyfish. They include specialized structures for sensing light (eyespots) and movement or direction with respect to gravity (statoliths). The 'eyes' are most complex in the Cubozoa, resembling the image-forming eyes of squid, octopi, and vertebrates.

Coronatae	Cubomedusae	Rhizostomeae	Semaeostomeae	Stauromedusae
		Cassiopea subumbrellar view (click to enlarge)	Aurelia exumbrellar view (click to enlarge)
		Mastigias subumbrellar view (click to enlarge)