We've been raising two young mantis shrimp that we had found while wading the flats several weeks back. This one had been occupying a hole in one of the rocks in the tank, but the other one recently found the hole and for some reason this guy moved out. We see it in several different spot in the tank - I guess it is trying to find another comfortable spot.
It has been a good time to take a picture of this recluse. This crab on the other hand is always out.