Hitchiker Crab ID?

[dbartkow]

Finally caught a crab that I have been watching for a couple of weeks. Over that time, I have only seen his claws sticking out of different pieces of rocks. But I have never been able to see his whole body. Just today I say some claws sticking out of a small piece of live rock I have that doesn't have much on it. So I took it out and droped it in some freshwater. He came out after about 10 minutes. Anyone have any idea what type of crab this is and if they are harmful? See the two images below (same crab).

I appreciate any insight - if I should put him back in the tank or get rid of him?

Thanks,
Dave

 

[650-IS350]

looks like a typical crab that would start to demolish your tank as it grows... looks like a teddy bear crab of sort eh'.

I don't trust ANY crabs... just snails....

http://home2.pacific.net.ph/~sweetyummy42/hitchcrabs.html