acro crab or crab of doom?

[fishieness]

hello. i just got a really nice millipora at my LFS. and there was a small white acro crab in it that was jsut a riot. i walked over to the tank and he threw out his claws and threatened me. he's quite the character. But now i got it home in my tank and i see there is another crab in there. he is a bit bigger and beefier. he looks almost like an emerald crab in shape, but he is a little hairy. and i have herad a lot of that hairy crabs are bad, but the thing that worries me most is his pinchers are like the crusher claw on a lobster. you konw the realy big one with the molar-like teeth? im wondering if any crabs will eat acros and if that is why he is there. ill try to get a pic otnight. I dont kwno if ive heard of a crab that feeds only on sps corals, but im jsut wondering if you guys thing that pincher is to chew up my millipora or jsut for scrapeing algae off of rocks?
thanks!

 

[goose3five]

I have two emerald's that sound just like what you are describing, hair is on the six legs and the main forearms with pincers are massive with flat ends. They use these to scrape algae off of your rocks but they also will scrape everything else off (read coraline). I can tell you I wish I had never gotten these suckers as they are ravenous. I have caught them tearing into various corals. The only thing I can do to stop them is to feed them Sea Veggies every other day.

 

[fishieness]

yeah. at first i had thought it was an emerald.... but i didnt think they had the white molar-like teeth that this one did?
im thinking of jsut banishing it to my fowlr.
thanks for the input, i dont have too much crab experience as i never realy trusted them in my reef

 

[sharkbyte1023]

Get a pair of tweezers and get it out. It should have blueish eyes as well. I have watched them on a lot of my acros and they eat the tissue. The other is safe and will keep the algae off and predators away. Good luck.

 

[mr_bill]

I'd remove the crab, see if it eats meat by putting from cut shrimp in front of it. Any crab with serrated claws like you described is usually preditory.

 

[ct_vol]

I wouldn't worry about it if I were you... It sounds like a mithrax crab to me... The green mithrax is also known as the Emerald crab...

I have a few red mithrax... The hairy one you want to worry about is a Gorilla crab... You can identify them by the black pointy tips on their claws... Very unmolar like...

 

[fishieness]

Originally Posted by Mr_Bill
I'd remove the crab, see if it eats meat by putting from cut shrimp in front of it. Any crab with serrated claws like you described is usually preditory.
yeah, that is exactly what i was worrying about. i banished him to my 29 gallon with my valentini puffer, my fuzzy dwarf, and a small moroon clown whose pastime is beating the crab out of my magfloat.
and now, it def wasnt an emerald crab. his body shape was simila, but he was definatly different