WHATSTHATFISH
Jellyfish & hydroids

Upside-down Jellyfish

Cassiopea andromeda

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

VenomousKeep your distance
Adult
@greatwhite · Sydney Aquarium, Australia · April 20121 / 10
01

Overview

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

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.

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How to identify

Body shape
fingers

Tap any trait to see other fish that share it.

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Habitat & where to find it

  • Range · Indo-Pacific
  • Country only · 10
LIVES IN

Found in shallow waters, over mudflats, sandy bottoms and seagrass beds of shallow lagoons and mangroves.

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Adult photos 10

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Discussion

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    ALL STAGES
    FOR THE MARINE-BIOLOGY CURIOUS

    Deep dive

    Taxonomy

    1. kingdomAnimalia
    2. phylumCnidaria
    3. classScyphozoa
    4. orderRhizostomeae
    5. familyCassiopeidae
    6. genusCassiopea
    7. speciesCassiopea andromeda (Forskål, 1775)

    SourcesWoRMSWikipedia

    07

    More in the family

    Rhizostomeae