I was in Isola d'Elba, an island off the coast of Tuscany, early last spring durring an enormous jellyfish bloom. At about mid-afternoon, before which the waters had been essentially clear of jellyfish, the area became completely swarmed all in about a period of twenty minutes. It consisted almost entirely of one species, which were obviously a type of comb jelly but whose description does not match anything I have been able to find on the net. They looked like Mnemiopsis, but were pinkish-orange in color (and relatively opaque), about twenty centimeters in length, and were covered in conicle, spike-like protrusions.

Among these were also a few individuals of a couple other species I have not been able to find information on. These include a type that was the exact size, color, and shape of a chicken egg, and another which was flat and resembled an elongated, outstretched pair of wings with a span of about 160 cm.

All of the species I have listed above were bioluminescent, emerged at the same time, dissolved easily to the touch, and did not sting (these being traits of jellyfish that live in the abyss, which therefore should not have been in shallow water to begin with). Unfortunately, I did not have a camera at the time and thusly can only describe them as best I can, but any information you might have on them would surely put my curiosity at ease.