The first time I saw these photos I had no idea what I was looking at. This coral sort of looks like a Bubbletip Anemone, but the details aren’t quite right for it to be Entacmaea. The surface texture of the tentacles is different, and a few even seem to be branched. Plus, the heterogenous size of the tentacles and their arrangement relative to the septa don’t correspond with anemone morphology. The habitat is all wrong as well. These were found on a boulder-strewn volcanic sand slope in Bali at a depth of 30 meters, not some sunny, shallow reef flat where Bubbletips naturally abound.
But take a moment to orient yourself and you’ll realize that this is actually just a plate coral, albeit, one which has grossly inflated its tissue. A “Bounce Plate Coral”, to use the aquarium parlance of our times. You can even see in the above photo what appears to be an anthocaulus which is still attaching this juvenile to the substrate.
These were observed during a morning dive by the talented marine photographer and author Andrey Ryanskiy, who graciously shared his interesting find. We featured some of his work earlier this year when recounting the amazing tale of the benthic siphonophore, and hopefully 2018 will bring with it many more of his unique discoveries.