Unidentified Critter

[BriGuy]

Sorry not able to get a picture of this; but can give details on this adventure. For the past 2 months I have been losing at least one small hermit crab per week in the tank (29g BC), at the same time I have been hearing a snapping noise from the tank. So after talking to everyone under the sun, it sounded like a pistol shrimp or a mantis shrimp. About 2 weeks ago, I said to myself time for this guy to go; so pulled the rock I believed he was living in out of the tank; tried the club soda trick and nothing of that sort came out. Today, I actually saw something going after one of my crabs; (of course different rock) I was not able to see the whole thing since it was faster then heck. But from what I could see it looks like a brown wolf spider (I know they dont swim in salt tanks, or do they?), all I was able to see was a few (4) brown legs that were about 3/4 of inch in length. I have few small brittles stars in the tank and this looked nothing like the sort. And thinking back 3 months ago I had an emerald crab that was found dead and torn apart. From looking at the "Marine Invertebrates" book the closest thing I can see in there that looks like this critter is a "Sally Lightfoot Crab" (Percnon Gibbesi) Pg 263. Anyone else have an idea, I tried some club soda on that rock a few minutes after seeing it and nothing came out. It moved to fast to be a starfish (unless it is on crack).

Thanks,
BriGuy

[JLiu]

Sounds like you probably have one of the shrimps as well as a gorilla crab.