Unknown crab variety

[gupebreedr]

I was sitting here at my computer reading various Nano-reef threads and happened to look up at my 10 G nano and saw this unusual looking critter. Actually I first noticed it two days ago and thought it was a piece of sponge that was somehow dislodged. It moved in a up and down fashion which I thought was just the currents moving it. Well, I forgot about it and just now saw it again but in a different location and again it was moving up and down. Upon closer inspection I noticed legs and attemped to remove it but it moved under some LR. I waited a few minutes and it ventured out into the open where I quickly netted him.

As you will be able to see in the pictures, he's bright orange and has some red algae growing on his back. It's size is slightly smaller then a quarter. Oh, and it does have a hard shell.

Any clue as to what it is? I am going to put him in the sump of my larger tank at least until I have a better idea as to what it is. Any help would be greatly appreciated.

 

Thanks,

Rob

[gupebreedr]

Here is another pic showing him on a plate.

[gupebreedr]

Here is a third picture showning him upsidedown.

 

Again, any help on this is appreciated.

 

Rob

[lizbeth]

I don't know what he is but he is very pretty. Too bad you live so far away...if you didn't want him I would take him.

[LiQuiD]

Get it out of your reef! That is commonly known as a decorator crab or sponge crab. They are called "decorator" and/or "sponge" because they "decorate" their shells with "sponges" or whatever other coral they can find and rip out. I have one of these in my fish only with live rock. Well, it has a few coral in it considering the low intensity PC's that were used to keep the coraline on the LR. Here is a picture of it from another thread I had posted it on. As you can see, it found a couple zoo patches and a piece of sponge. Before I banished it to the FOWLR, it was in a larger reef when I noticed it with a Acropora frag on it's back. They are VERY destructive. Trust me, you don't want it. Besides, they get over a foot in size.

[Bucket o Chum]

They are safe when real small but when they are beyond an inch they will start plucking your precious inverts for decorations. How big is it?

[gupebreedr]

Hey guys,

Thanks for the info. This critter was removed from my nano and placed in the sump of another one of my tanks. I'm glad I was able to get it out without too much of a problem. He's only the size of a quarter but I surely don't want him destroying any of my livestock.

 

Thanks again for the help,

Rob