Could somebody ID this crab?

[pufferdady]

So, I was rearranging my tank today and I found this guy under a rock. I'm about 95% sure that he's been in the tank for a year or more I have caught him scampering away into the rocks before. I've also seen his leg in a hole in the rock that I found him in. I've never had any trouble with corals getting eaten that I've noticed anyway. I would like to know if he is or could be harmful to any inhabitants(snails, hermits, fish, ect).

 

[returnofsid]

Looks like it might be a Sally Lightfoot. Some say they're reef safe, others disagree. I used to have one in my 46, for several years, with no problems.

 

[braddo]

Check out http://www.chucksaddiction.com/hitchcrabs.html, it looks like some type of xanthid. We had one in our tank for a while burrowing in the rocks and he was a prime suspect in some missing Zoas and Xenia.

 

[lizardarm]

It's a black mythrax crab. I've got several in my tank now, all hitchikers. Never seen any of them doing any damage. They are quick to eliminate a dead fish for you. Some say not to trust them, that as they get bigger they may become less "aquarium friendly", this is probably not bad advice. My experience- they seem safe.

 

[lizardarm]

Also, take a good look at the tips of the claws- kind of like little scooper/scraper type deals. They use them to scrape algae off the rocks. But then as you move further up the inside of the claw, you can see that there are sort of dull serations/pokers type deals; probably intended for griping flesh.

 

[pufferdady]

Yep, from the picks I googled you're right liz, it does look alot like a Sally too but the body is definately wider like the mythrax. Thanks for all the info guys, I've decided as long as I've got it out I might as well leave it out. If I had a refuge I'd throw him in there but.... Kinda feel bad for the guy but, not as bad as I would if he started causing trouble, plus there's no way I'll ever catch him again.

 

[Damsel13]

I was going to say actually I am saying Wow! I am ipressed you caught him!

 

[cookie]

I have one in my tank that I cant catch...how did you cath yours??

 

[pufferdady]

I actually just set up a new tank and moved a bunch of corals into the new tank. The night I caught him I was totally rearrnging the tank to get better flow. I had a bunch of rubbermaid tubs out for putting LR in. When I lifted one of the pieces I saw him tuck up under the piece in my hand. I don't think it was the piece that he lives in because I've seen his legs through the holes in another piece. I don't think he was able to hide inside the rock like normal. I put it in the tub, grabbed the glass and got him to jump into the glass. So, short story long it was luck and the fact I had the tank torn apart.

 

[alki]

Yikes! I mistakenly bought a sally lightfoot crab. It was basically a giant spider that would scare the crap out of my wife all the time. Not real fun putting your hand in a tank with those guys...

Asta La Vista!

 

[lizardarm]

I've found that if you hold a hunk of shrimp or fish or whatever in front of them with a pair of tongs, they'll grab on pretty quick. You can yank them out into the open that way and grab them with a net or whatnot.