Sorry, can't get a pic because this thing seems photo sensitive. Every time I turn on the tank light or flash a light inside the tank it zips back in its hiding hole.\n \nIt seems to be a worm or appendage coming from a whole in a small rock with some mushroom coral on it. It seems to retract too fast for a worm, it will be out a good inch, a flash a light and it retracts in a millisecond. What I can see in the darkness, it does not seem to be a bristleworm, I don't see bristles, and it seems dark in color. Anyone have any suggestions? It is on the same rock I discovered my two baby Featherduster worms earlier today, but in a different spot.