Found worldwide, moon jellies are distinguished by the prominent “clover” in the center which is actually their four gonads. It was once thought that moon jellies were all part of the same species, Aurelia aurita. In recent years, thanks to advances in genetic barcoding, multiple moon jelly species have been discovered.
A common cooler water jelly, Lion’s Mane jellyfish emerge from embayments bordering Nantucket Sound during the early spring. While they start out small, they can grow to be one of the largest jelly species in the world, with their bells reaching 7 feet in diameter in ideal conditions. The largest Lion’s Mane jelly discovered was found off the coast of Massachusetts in 1865 and was recorded to be over 7 feet in diameter and 120 feet in length with its tentacles..