White Crab with diamond shaped mark on back ID?

[RichMacys]

I have an unexpected addition to my new 15gallon. It is a small crab (less than a dime in size) that is very light tan almost white and has two spots on its shell (one larger diamond shaped one and one smaller dot towards the back) He is NOT HAIRY. He is not nocturnal as he is out and about midday with the halide on. He will dig into the substrate when he notices me moving around the tank. He has fairly large claws that have brown pinchers. Just wondering if anyone has this same crab or may know what it is. It came in on some new live rock.

Thanks for any help.

 

[Len]

Hey Rich,

Unfortunately, I can't ID this critter (too many crabs!), but due to the description of large pinchers, I'd remove him if you could just to be safe. Most crabs with large pinchers are scavengers, but they will also prey on targets of opportunity such as sleeping fish.

Sorry I couldn't ID it. Any chance taking a pic of it?

Off on a tangent: I once had a crab in my tank that was a stowaway. It was active day and night and had really large pinchers. When it was small, it caused no problems, but after 2 years, it grew to over 4" and I started losing fish. I came to the conclusion my crab was making meals of my fish at night. After removing it, no more fish disappeared mysteriously for months after.

 

[TZL]

a pic would help greatly

I have an unexpected addition to my new 15gallon. It is a small crab (less than a dime in size) that is very light tan almost white and has two spots on its shell (one larger diamond shaped one and one smaller dot towards the back) He is NOT HAIRY. He is not nocturnal as he is out and about midday with the halide on. He will dig into the substrate when he notices me moving around the tank. He has fairly large claws that have brown pinchers. Just wondering if anyone has this same crab or may know what it is. It came in on some new live rock.

Thanks for any help.