Discovered New Crab...

[jamesrm]

I have a 125 reef tank that has been setup for 2 months. I added 80 lbs of live rock that had all kinds of life on it, but I didn't notice anything large scale until now. Sorry, I was not able to get a suitable pic due to the LED lighting that I use. I noticed a new crab, about the size of my arco crab (3/4 in leg to leg) or so. Its legs are hairy and shell has lots of small bumps. I know its not big enough to do much damage, but also hairy legged crabs are generally bad for the tank.

So, any idea what it is? And, even if I determine it to be unwanted, how in the heck do I catch it?

 

[pokmijn]

since its a crab shouldn't it be easier to trap

 

[pat8you]

Take a tall glass and tilt it with the opening facing where you saw/ think the crab might be. Put a small piece of shrimp or fish or chunk of food in the bottom and wait. They usually can't climb back up the smooth surface of the glass.

 

[Floyd R Turbo]

Check out Myth #7...might not be an issue

Mything the Point: Part Two by Eric Borneman - Reefkeeping.com

 

[Ziggy953]

Could be a mithrax which is not bad but not really good either. I would catch it for better inspection and pics. If you do catch it you can always put it down in your sump.

 

[iDream]

yeah it sounds like an emerald crab, ive seen some with hairy legs on occasion and see some in my LFS from time to time

 

[pat8you]

Check out Myth #7...might not be an issue

This is interesting and i suspected that "hairy leg crabs" probably covers a wide variety of different crabs just like they say in the article. In my opinion though most people (including myself) don't have the knowledge to accuratly identify species of crabs. I don't think benifits of it possibly being a "good" crab is worth it considering the risk that a "bad" crab poses on our tanks. My rule is if it has claws and is not the little blue legs i put in the tank; it gets banished to the sump.