Upside-down jellyfish

Cassiopea xamachana · The upside-down jellyfish is a jellyfish that lives in warm parts of the western Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico.

Upside-down jellyfish
Photo: Marco Almbauer, Public domain
Upside-down jellyfish
Photo: Bjoertvedt, CC BY-SA 4.0
Upside-down jellyfish
Photo: No machine-readable author provided. Bastique assumed (based on copyright claims)., CC BY-SA 3.0

Taxonomy

KingdomAnimalia
PhylumCnidaria
ClassScyphozoa
OrderRhizostomeae
FamilyCassiopeidae
GenusCassiopea
SpeciesCassiopea xamachana

Where it lives

Warm western Atlantic, Caribbean Sea and Gulf of Mexico, in shallow bays and lagoons.

Fun facts

  • This jellyfish rests upside down, with its saucer-shaped bell underneath acting like a suction cup to hold it steady on the seabed.
  • Instead of one central mouth, it has numerous oral openings in its tentacles that connect through channels to the stomach.
  • Tiny photosynthetic algae living in its jelly give it its bluish-grey or bluish-green color and provide part of its food using sunlight.
  • If disturbed, these jellyfish may pulse their bells and rise into the water, then soon flop back down onto the seabed.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).