Brief Life Cycle Overview
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The moon jelly has two life phases: the sedentary polyp stage, and the free-living medusa stage. When sperm and egg unite, fertilization produces a planula larva with cilia. This will then settle into the substrate where it will develop into the polyp. As the polyp grows, it will eventually form into a budding polyp, which will then give rise to the ephyra. This juvenile form will continue to develop until it reaches the adult medusa.
Detailed Life Cycle Overview: A Dramatic Tale
The video below does an excellent job of conveying the life cycle of the moon jelly in captivating, real-life footage.