Photos of thiis very small sea anemone with red tentacles and a grey/purple column were sent to us recently. It was adhering to a small sea snail which was feeding on seaweed in a tidal rock pool near Baleena Bay, Wellington. There were lots of Actinia tenebrosa on the rocks nearby, which have very similar tentacles, but the observer had not seen them on shells before, nor that colour column and foot.
This is a brand new baby Actinia tenebrosa. The adults brood them in their gut cavity until it is time for independent life. Then they are released to take up their new home, usually quite close to the adults.
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