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INDO-PACIFIC Coral Reef
The varied Cnidaria include the reef building corals, the sessile anemones, and the free floating sea-jellies...
Phylum Cnidaria: Sea Jellies, Corals, Anemones
Class Scyphozoa: 'True Sea-jellies'
These are Jellyfish that have eight divided arms hanging from the bell, rather than tentacles
Family Cassiopeidae: 'Upside down Jellies'
Cassiopeia ornata, 'Upside-down Jellyfish'.
Class Anthozoa: includes Stony Corals, Soft Corals, Anemones
Sub-class Ceriantharia: Tube-dwelling 'Anemones'