Triton’s trumpets are snails and their shells are the second largest in the Indo-Pacific. They can attain a length of 20 inches. The colorful shells are also quite beautiful, especially when they catch the light filtering down from above.
These snails eat echinoderms including Crown-of-Thorns stars, which feed on corals.
Graham's Island 
Fantastic sighting and photo Graham. I hope you don’t have to wait another seven years to see the next one.
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Who knows? One of the joys of snorkeling is never knowing what I might see.
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Beautiful sea creatures, Graham. Nice shot of it too!
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That’s the second one I’ve seen in my seven years here so they’re not exactly littering the sea floor.
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