It is a finger leather coral. The tank has been set up just over 7 months. 46g. The coral has a white area where one of the fingers has started to almost peel away if you like. I have seen it shed its skin once and it didn't look like this. I have a mushroom leather, clove polyp, a small colony of zoas and a sun coral. All these appear to be very happy and thriving. The finger leather has grown a lot since a first got it.
Here is a pic in its retracted state
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