it is a xanthid...has dark tip claws. <knock on wood> does not disturb anything that I can tell. The tank has been up and running with this live rock for more than a year...so he is just growing and growing! I have only had 2 fish disappear, a pair of neon gobies...guess it could have been "it". LOL
It is one freaky looking thing though. It is like 3"....have to go measure. He is near side glass of tank now.
Sorry, I should have been clearer. Gorilla crabs are not xanthids, but someone in their infinite wisdom decided that they would call the strange looking crab they found a "gorilla" and now the entire hobby refers to xanthids as gorillas.
I know it is a xanthid because of the dark tips on the claws (I think that helps ID it....)
It has been in there a long time....Do I get rid of it?? Into the sump???