Xanthid Crabs?

RyanG

Reef enthusiast
Well in the process of messing around with my rock I saw briefly a hairy Xanthid style crab (flatish and disk like) It was somewhere between a quarter and a fifty cent piece in size and probably 1/2 inch thick. I cant get a good look at him let alone take a pic at the moment. It is hairy and a brownish-gray color very similar in color to rock that isnt coraline encrusted. Does anyone have any idea with this description? Should I leave him be or take him out? Im actually kind of excited to find hitchhikers like these!
 
Its just in a live rock storage tank for now. Do they typically use the same cave? He might be lost again if not.
 
Does it look like this? This guys been in my tank since day 1 and has never done anything but eat algae at night. i've spot him right next to my zoas, mushrooms and SPS and he's never touched em. He was very small when I first saw him while putting the LR in my tank.

Crab0011.JPG
 
mine tends to stick around in the same area for a couple of weeks sometimes until theres no more food or he's getting to big for his hiding spot.

Oh and i've never gotten a positive ID on mine.
 
Any tips on getting him out of his cave without harming it so that I can get a pic for ID purposes?

NewbReefer I cant really even get a good enough look at it to tell its similar in color?!?! It did pop at me a little when I was fussing with the rock. Im positive that it isnt a mantis or pistol though.
 
to get mine out for ID i took the rock out and put it into a small bucket and with a small blunt object i carefully proded the rocks other caves opposite from his typical entrance, my rock has holes all over it and if theres a cave entrance it probably has 5 other ways in or out. i've also heard of people placing airstones under the rock to get things to come out of there rock, never tried it though.
 
Hairy crabs generally = bad. :)

Your best bet is to isolate the rock that you THINK he's in. Then lure him out with food, or just watch it carefully at night. Chances are you'll spot him again.

You can do a quick freshwater dip of the rock. This will usually make the crab come shooting out pretty quickly, but in that case you risk killing the crab and your rock.
 
i read a couple things in wetweb yesterday and some people have trapped em by putting a small glass or container in the substrate and putting some food in that. the crab (if it falls for the bait) will drop inside the cup, eat the bait then won't be able to climb out the slippery sides. if you try that i'd place the cup near where you last see him.
 
I had one of those hitchhiking crabs for about 5 years.I was to lazy to ever remove it.It was tiny(1/2'') when I first notice it,several years later it was around 4''.It love eating snails,always notice empty shells near its den.It never bothered the shrimps or fish,though.

I would remove it.
 
reeffreak, what about your corals? sounds just like mine, less than one inch when i first saw him and now is 2". never noticed him eating any snails though, I've lost snails but i also have a large hermit that would have gotten to em before the Xanthid.
 
Never touch or lost a coral to that crab.It stayed mostly hidden during the day,one creepy looking crab.Those eyes,mine had blood red eyes and how the claws folded flat making them look like part of the crab's shell.
 
Never touch or lost a coral to that crab.It stayed mostly hidden during the day,one creepy looking crab.Those eyes,mine had blood red eyes and how the claws folded flat making them look like part of the crab's shell.

yeah all crabs are omnivores and may pick at corals if they are going hungry but mine hasn't so much as taken a second glance at a coral (probably cause im still trying to get my algea under control) but once i get my pod farm full of rock he may find himself in there for safe measures. he could probably take out my zoa colony in one night if he found how tasty and meaty they are. If i can't get what little hair algea i have under control soon before it gets outta control i may be picking up some Emeralds.
 
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Well I think I have found a good home for the little guy. Im 99% sure that its a gorilla crab. Im going to give him away, I have to cycle my system and I would hate for it to die. The guy has a 30 gal crab utopia set up and hes looking for unusual crabs. Im bummed that I need to get rid of it but its for the best!
 
When I finally get him to drop into the glass I will make sure to post some. Hes grey-brown hairy as hell, with black claws with red tips. Little tiny eyes and a big gaping mouth! OH yeah his legs are white on the undersides too. Stubborn little fella too. Hes got himself wedged into the mouth of the cave and even with some gentle prodding was holding his ground firmly!
 
it sounds very similar to mine although i saw mine last night and he had some sort of green thing on his belly anyone ever seen something like that?
 
crazy critters! I dont think i ever had a crab hitchhike on a rock, however bifff had the coolest hitchhiking crab ever. good ol sebastian!
 
Yep, good ol' Sebastian! Good times! He disappeared into the abyss of my tank a while back. I don't know if someone ate him or what. I was very sad to see that one day he had left his stylo home, never to return. You don't come across neat finds like Sebastian every day.
 
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