its not a sally the claws are too big. i've have been keeping sally light foots for some time now had one up to 6" across until it climbed out of tank.I'm looking at marine atlas and it could be atype of runnercrab is it hairy ? did you buy it or did it come in on live rock. can you take it out an place it in sump for observation so you can see its characteristics, what it eats, harms inverts etc.
I rarely ever see him. It was a rare occasion to actually see him out on a rock where I could take a picture of him. He came in on live rock. I think he might be hairy but I don't remember that well.
From what I can remember he is light green and looks slimy and not hairy. He moves his body and stuff around really fast. But he doesn't physically move locations fast. He stayed around the same area, he just looks like a crab that is on crack :shock: .