did this crab do the crime?

[tonytran]

Guys, we may have a murder scene on our hands....Or do we? Im not sure, can someone ID this crab? I've searched and searched with no luck on what this crabs name is.

I noticed doctor wrasse missing 2 days ago and suspected that it was either my carpet anemone or this crab who may have been responsible for the disappearance of the wrasse. I have never seen this crab come out from beneath the sand, but today it was sitting right on top of it. Of course i took a closer look and what do u know, hes devouring the remains of the cleaner wrasse!

Now he is definitely a prime suspect but still innocent til proven guilty. Maybe the fish died for other reasons and the crab just was playing scavenger? So my question is, what is this crabs name and is he capable of killing fish? If so, I need to remove ASAP. I've only had him a week so dont know him too well.

P.S. is this guy reef safe? Im fearing for my crocea right now!

 

[LeslieH]

Why don't you take him out, put him in a bowl, & get a picture of it from above? He can stay there or in your sump for a while until we get an id. Better pics will help us figure out if it's primarily a scavenger eating remains or a predator that should be removed.

 

[Doc Hammer]

Do you know if he came in with LR or did you buy him? If from LR, from what waters is it from?

 

[ReefJunkie21]

That thing has a guilty face. Stop all proceedings and place him under sump arrest.

 

[tonytran]

Well, I bought him from the LFS, so he's not a hitchhiker. He's about 1.5" (not including legs) and is pretty quiet in the aquarium. Like i said, i've never seen him come out from the sand until now. Ill put a warrant out for his arrest.

 

[Doc Hammer]

Ah ha! Looking at my Reef Creatures Identification: Florida Caribbean Bahamas book, he has a very striking resemblance to a Flame Box Crab, or Calappa flammea and I don't think it did the deed. Those big claws are used to crush the shells of hermits.

 

[LeslieH]

Tony - are the 4 pairs of normal legs flattened? If so you have a crab in the family Matutidae, either Ashtoret or Matuta. Take a look at this earlier RC post which has some very nice pics:
http://www.reefcentral.com/forums/s...44&perpage=25&highlight=ashtoret&pagenumber=1

Assuming that it is, here's a paper discussing a feeding study:
http://www.publish.csiro.au/?act=view_file&file_id=MF9880193.pdf&xdata=

Basically they eat small crustaceans & molluscs and scavenge. Crabs in tanks with big shrimp & fish were never seen to attack healthy fish/shrimp but they would take sick or injured ones.