'Cotylorhiza tuberculata' is a species of jellyfish, of the phylum 'Cnidaria', also known as the Mediterranean jellyfish or fried egg jellyfish. It is commonly found in the Mediterranean Sea, Aegean Sea, and Adriatic Sea.

It can reach 40 cm (16 in) in diameter but is usually less than 17 cm (6.7 in) wide. It seems that this jellyfish's sting has very little or no effect on humans. The cnidarian's smooth, elevated central dome is surrounded by a gutter-like ring. Its marginal lappets are elongated and subrectangular. Each mouth arm bifurcates near its base and branches several times. In addition to some larger appendages, there are many short, club-shaped ones that bear disk-like ends.

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