Upside-down Jellyfish (Cassiopea andromeda)

Also known as Upside-down Sea Jelly, Sea Jelly, True Jellyfish


Also known as Upside-down Sea Jelly, Sea Jelly, True Jellyfish.

Found in shallow waters, over mudflats, sandy bottoms and seagrass beds of shallow lagoons and mangroves. Often in the sun, they lie on their backs and so look more like anemones or sea stars. These jellyfish rest upside down, to get more light to their tentacles which collect algae which in turn provides food for the jellyfish through photosynthesis.
They feed on zooplankton.
Diameter 30cm
Depth - 0-30m
Widespread Indo-Pacific

Sometimes these Jellyfish are picked up by decorator crabs and ride on their backs as defense against predators.
Although their sting is very mild!
Named after one of Greek mythology's treacherous queens Cassiopeia!
Cassiopeia is also a constellation in the sky.

Jellyfish are 95% water.
They have no heart, brain, blood, or gills. The body of the Jellyfish is called a bell. They do have a mouth, tentacles and arms around their mouth. They use their arms around their mouth to help sense and find food that ends up inside their mouth.

Their predators are Sea Turtles and Sunfish. Ref:


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