Mangrove Upsidedown Jelly

Cassiopea andromeda is carnivorous and eats small animals from the sea or just pieces of them after it paralyzes its prey with its mucus and nematocysts when they are released. This jellyfish also lives in a symbiotic relationship with photosynthetic dinoflagellate algae, zooxanthellae, and with shrimp. Zooxanthellae live in the tissues of the ventral surface of the jellyfish and are responsible for its color. As the zooxanthellae obtain food for the Cassiopea andromeda, in response, it gets the sunlight that is necessary for the algae. The shrimp lives in the jellyfish's tentacles and protects it by removing parasites. In exchange, Cassiopea andromeda offers protection to the shrimp. This symbiotic relationship is called mutualism, where both species benefit from their interactions.

As a cnidarian, this jellyfish employs both asexual and sexual reproduction. It reproduces by budding when it is in a polyp form. When it is in a medusa form, it reproduces sexually. The medusa female produces the eggs and keeps them. As the male produces sperm and releases it into the water, the female uses its tentacles to capture the sperm to fertilize its eggs.

The species can deliver a painful sting. Symptoms include mild pain, rash, and swelling.