Crazy looking crab showed up today!

I was looking in the tank today and this crab jumped out and scared the hell out of me.

Anyone know what kind it is, is it dangerous. It was eating off the shell of a small hermit, didn't try to eat it though.

The crab is about the size of a silver dollar.

I have no idea how it got in, I've never seen it, and I haven't really made any recent additions to the tank. I highly doubt it was hiding in my colt coral.

It's probably been hiding for months now.

Sorry this is the best pic I could take, he was moving in the shadows.

 

Not a clue, but the rule of thumb is that hairy legs = bad.

Sort of like with girls... (I can just feel the negative rep coming... )

On a more serious note, I hope someone else can ID it.

 

Me too!

Should I try to isolate it, if I can?

I've been looking all over online trying to find out what this thing is.


Oh, my SG is back and everything seems to be ok. Thanks for the algae offer, I'll see if I can swing down there, I'll get back to you.

 

You can try googling characteristics of this crab (i.e. hairy crab, spiny crab, etc). If you google "hairy crab," you get results resembling your crab, but not sure as the picture is not as good of an image, but pretty clear. Obviously eating algae but most crabs tend to be opportunistic, keep an eye out for that guy and corals.

I've found crabs in my reef that I didn't even know I had as well. I recently discovered I had a shy face crab when I tore down my reef several months ago. It's got really bloodshot red eyes, it's pretty cool. ;D

 

Im with Blade on this one, looks like some sort of mithrax crab. If you have a fuge stick him in there but i would definitely get it out.

Marc.

 

this looks alot like your guy here:
Hairy crab image page

 

Closest image I've seen.

I'm going to get him into the fuge, or try anyway.

Thanks for the help everyone!

I'm still going to see if I can find a better match.

 

I agree Marc. Reminds me of my old Emerald crab.

Mine was fairly well behaved and actually helped a bit with valonia.

 

Yeah so did mine.... until he started eating chunks out of my clown fish.

Marc.

 

It is an Emerald Crab(MITHRAX)! They have hairy legs as well. They are reef safe! I have three in my tank and they are the size of a Silver Dollar. I've never seen them as big as they are in my tank-but they give me no problem and don't bother any of my livestock or corals! I love these crabs. For some reason, I can't keep Sally Lightfoots alive in my tank, unfortunately as crabs are cool to watch and very unique.