Crab ID help

[showtime305]

<span style="color: black;">I but a nice small acro colony today and notice this crab on it as I got ready to place it in the tank. At first I was thinking it's an acro crab but as I was watching it pick at the acro decided to get an ID before I lose all of my coral. I don't have a great camera so I hope these pictures are good enough for an ID.</span>
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[cdub]

doesn't look like any of the crabs i've seen before. i would toss it in your sump until someone can give you a positive id.

 

[glxtrix]

generally if it was in the acro its an acro crab, although the hairy legs are kinda throwin me off....it almost looks like an emeral crab, but dont take my words on that. Ok, I guess I dont offer any help, lol. Hope someone can get it for you.

 

[showtime305]

The hairy legs and I noticed it picking at the coral caused me to take it out. I'm seeing so post saying some acro crabs do have hairy legs but who know if this is one of them.

 

[FutureInterest]

Even if it is an acro crab, there is some debate whether they are benefitial or detrimental to the coral they host in. Some people have noted acros becoming necrotic, starting in the area the crab typically hosts at. Other people have claimed that corals with acro crabs grow better than corals without... In my opinion, when in doubt... I KILL IT!!! That being said, I have a lil bandit acro crab in an ugly acro...

 

[sj miller guy]

It looks just like one of my emerald mithrax crabs I got from Capp. Bay a while back. Although yours looks more brown than green.

 

[FutureInterest]

The best way to figure out if he's a good crab or a bad crab is to get a good look at his claws. If they're serrated he's a bad boy and should be exiled to the fuge or liberated in the chatahoochee.

 

[xyzpdq0121]

FutureInterest;50530 wrote: liberated in the chatahoochee.

Ummm negitive ghost rider....


Looks like an emerald crab....

 

[showtime305]

<span style="color: black;">The black tips on the end of the claws and blue eyes make me think it's not an emerald. I've never seen one with those attributes. It would be nice if it is though.</span>

 

[wbholwell]

Looks exactly like one I had grow out of my liverock. I did a lot of searching, and concluded that he was a red version of an emerald crab. I decided to leave him in my tank, but I haven't seen him in a long time. The pincher tips were flat, and I never saw any evidence of damage to any corals.

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[showtime305]

FutureInterest;50530 wrote: The best way to figure out if he's a good crab or a bad crab is to get a good look at his claws. If they're serrated he's a bad boy and should be exiled to the fuge or liberated in the chatahoochee.

Upon futher review one of the claws appears to be flat like and emerald crab claw and the other is pointed but does not appear to be serrated.

 

[showtime305]

<span style="color: black;">Ok. After an hour of searching I finally have an ID for this bugger. This is an Acro crab (Cymo melanodactylus)</em>. The only problem is that it appears to be one of the hit and miss acro crabs. Some people say they are fine others say they have seen them eat some of the acro. I like the way it looks and so does my wife so I'm considering giving it a shot. As for now the crab is in QT. I'm not seeing any polyp extension from the coral right now so I'm going to give the coral a few days to acclimate to my tank. I'm hoping that the lack of polyp extension is not because of the crab but only time will tell. If I notice a decline in the corals condition once I add the crab back in, I’ll remove it for good.</span>

 

[wbholwell]

Oh, yeah, sorry- not quite like my crab.

 

[showtime305]

Ok. So after thinking about this last night I realized that there is no way I'm letting this crab loose around my corals. He/she is up for grabs to a good sump. I would rather not kill it since it's not the crabs fault it ended up in my tank.

 

[mfinch99]

What made you change your mind? Did you find some new info?

 

[showtime305]

After taking several good looks at the coral it came on I noticed several light spots all over the coral. I couldn't tell if it was bleached or if the tissue was scraped off but I rather give the coral a better chance to heal. I think the few people that had no problem with this crab had luck on their side.

 

[glxtrix]

lets just hope that those spots arent from AEFW's:

 

[showtime305]

Hmmm. I'll have to take another look at the coral. I examined it a few times with the tank lights on and again a few times with a flash light but never noticed any parasites. The lack of polyp extension does have me on alert though. I figured I needed to give it a few days to acclimate.

 

[tanner86]

Unless you absolutely know if it is a reef safe crab, I wouldn't place him back in your tank. I don't know how big your tank is, but in order to get him out again you will have to tear apart the entire system and still he might wedge himself inside a rock to evade capture.

I found a crab on my rock, in my 29gal, about the size of a pencil eraser. I made the fatal mistake of putting him back in my tank. He is still small and rarely seen, so I hope he is reef friendly.