HELP: Hitchhiker Crab ID

[dsagerman]

Was just able to catch this hitchhiker crab that came inside some live rock I recently got. Can you please let me know if gorilla or emerald crab and if it’s reef safe or should remove? I see it hanging around corals but hasn’t done any major damage in the 2 weeks it’s been in there.

 

[Evil1]

Looks like an emerald crab. Good CUC

 

[BristleWormHater]

Emerald crab, Mithrax sculptus. These are reef safe with cuation, 2/4 I have kept ended up eating coral and had to be removed. They can be decent hair and bubble algae grazers.