mystery crab

[MtReefGuy]

Can anyone I.D. this critter? Is it safe to keep in my tank? It seems to have blue color on the tips of legs. his body is only about 1/4" inch wide. Got it separated into the q tank for now..... found in a birdsnest coral...... any help is appreciated.

 

[Steve and his Animals]

Species of guard or coral crab. They spend their whole lives in an SPS colony (Acropora, Pocillopora, Stylophora, Seriatopora, etc.). They protect the coral from predators like sea stars and in return have a safe place to live, subsisting on coral mucus and other foods caught in the colony.

 

[Steve and his Animals]

Looks like Trapezia areolata if I had to guess a specific species.

 

[MtReefGuy]

So do you think i should I put him back? If he wont hurt the coral, I'd be inclined to put him back, but I didn't pay for him, so his welfare is secondary to the corals health. I can put him in another tank if needed. Thanks for your response. My first post here.....
Ken

 

[ISpeakForTheSeas]

So do you think i should I put him back? If he wont hurt the coral, I'd be inclined to put him back, but I didn't pay for him, so his welfare is secondary to the corals health. I can put him in another tank if needed. Thanks for your response. My first post here.....
Ken

I agree that it looks like a young specimen of Trapezia areolata, and yeah, I’d put it back in the birdsnest coral - Trapezia crabs are actually beneficial for their host corals.

 

[MtReefGuy]

Thank you both for the info, I'll put him back in the nest.