Another "What is it?" from our walks on the beach in Florida.
Answer:
This is a Sea Pansy (Renilla reniformis). It is actually a colony of individual organisms, and is a close relative to corals and sea anemones. The Sea Pansy is a filter feeder, collecting tiny bits of nutrients from the water. They are also strongly bioluminescent, glowing a bright green when you disturb one on the beach at night.
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