Crab ID Assistance

[cshouston]

I have a few hitchhiking crabs! I could use some assistance IDing them. For reference, the rock came from the West Atlantic, off the Florida Keys.

This one I’m not sure about. I’ve only seen it grazing on algae so far. It has very narrow claws.

This one I’m 99% sure is a porcelain crab.

There’s a third crab that I’m positive is a red mithrax because I already have one in there and they look almost identical. Are any of these a long-term threat I should attempt to trap and banish to the sump? Thanks in advance.

 

[Mr_Knightley]

The first is a baby gorilla crab, they eat coral and are big pests. The second is definitely a porcelain crab.

 

[cshouston]

The first is a baby gorilla crab, they eat coral and are big pests. The second is definitely a porcelain crab.

dang. I thought gorilla crabs had larger, broader and darker claws. This little guys claws are super narrow. I actually rescued it from going down the drain in my sink when I was trying to clean off some bubble algae that hitchhiked in. It pinched my glove and was hanging off of it. If it is a gorilla, I wish I had thrown it in the sump when I had a chance.

 

[ScottR]

I second that the second is a type of porcelain

 

[fishguy242]

with them hairy legs,beaty eyes,baby gorilla to me

 

[cshouston]

Well, I think I got rid of it... I tried to grab it with tweezers, but missed. I took some legs off, and then I’m pretty sure I squashed it when I tried to grab it out of the hole it scurried into. I managed to knock a rock over too and saw a little pistol shrimp scurry away. At least I’m glad it wasn’t a mantis making that snapping sound.

 

[cshouston]

Interestingly enough, I also banished the red mithrax to the sump and it looked an awful lot like the little guy in the first pic, just a lot larger.

Same narrow claws and wide set eyes.
Now I feel bad for possibly accidentally killing the baby crab since, as I understand it, mithrax aren’t a bad species.

 

[Maritimer]

I don't think that the little one was either a mithrax or gorilla, but something rather closer to the spider / decorator crab group, based on the shape of its carapace and claws.

~B.