Seriously big hitch hiker ID needed.....almost scary!

[crny1]

Well i saw this in a hole of one of my rocks last night. I couldnt get close to it before it would close up. So i shut all lights down in the house after the tank went out and waited about an hour and snuck up on it......still as soon as the flashlight came on it closed and i couldnt see anymore! It looks as if whatever it is has grow so big in the hole that it cant even get out. It is on a 18 pound rock or else i would take it out and break it near it to see what it is. It almost looks like a set of crabs arms blocking the hole. It will open up a little but as soon as i get near they close up tight. I even used a acrylic feeding rod and tried to move it or pry it out but let me tell you it has a firm grasp on the hole. With its arms or whatever in the opening of the hole i cant see any of the body to get a better description. I know its a long shot but i thought i would see if anyone might have an idea from the picture ....... sorry its the best i can get as far as a macro shot. Any suggestions? If its not ID'able then what should i do? Let it be and worry later about it possibly eating corals? This thing has some serious strength cause i cant pry its arms or what ever they are apart! Its almost like it would be a persons forearms together blocking a hole. Sorry for the bad description but its not an easy thing to decribe!

http://reefcentral.com/gallery/data/500/106516mini-micelaneous.jpg


Thanks for any suggestions or input as what to do!

Wes

EDIT: P.S. this thing is about the size of a dime (hole in rock is that big and it fills the hole completely)

[Letmegrow]

Just a harmless bivalve.

[crny1]

What is a bivalve? never heard of it......

[Kinetic]

a clam is a bivalve

[Letmegrow]

Or scallop, anything of that nature.

[crny1]

Well i did a quick search on google of bivalve's and i must say that i didnt come across any pics that looked like what i have. All the ones i saw appear to be more like a clam, oyster or scallop. This looks like a arm or a set of arms being used to block the hole. Maybe im an idiot but this just dont look like any bivalve that google or RC searches turned up...........

[sirreal63]

You can chisel it out if it worries you and you can do it w/o destroying the whole rock.

[hagfish]

I'd leave it. It does look like a bivalve of some sort. Or maybe a sea squirt. I doubt that guy is going to cause any problems either way.

[Letmegrow]

It could be a barnacle too,

[crny1]

Dont get me wrong Steve, I was not doubting you by no means. Just merely stating that none of the pics i turned up looked like what i got. Its not so much that i am worried about it. Guess it just a curiosity thing. Trust me if it was bad and was doing damage my 7 year old would be the first to tell me it was doing something cause he sits in front of the tank for hours on end with his little flashlight checking things out and looking for new things in the tank. Heck he even informs me about things and corrects me when im wrong! I think he has become a aptasia expert...lol. He is always correcting me when i say its aptasia and he says no its a manjo or a rock anenome! Now..... if i can only keeps his intrest in all this till its time for college! He even wants to have a class field trip to our house to show the kids our 3 tanks! wow...anyway back to the hitchhiker. Im gonna keep an eye on it and see if it moves around in the tank or stays put. from what i understand bivalves move around, correct? or did i read wrong?

Wes

[Dert42]

could it be a nude hermit crab that found a hole in the rock?

[Letmegrow]

It's just a boring, not like lame, but drilling type of clam.
The bury deep inside rocks. Sometimes if you get a cross section of LR you will find these guys smack in the middle of no where in the "solid" parts of the rock, with just the tunnles they bored to get there.

I would have to see it to get a better judgement.
The set of arms blocking it, is the foot or tounge or mantle of the bivavle, espeically since they are moving.

Look up barnacle, it could be one too, but they have fans that come in and out very fast like a porcelin crab.

You can second guess me all day long. Just don't be a troll about it ;) .

[dela]

Try stiking your finger in the hole to see what happens! :lol:

[DrBDC]

It looks like a bivalve of some sort to me too but the pic is a little hard to see well. A lot of different things can hitch hike though. I have a unknown type "lefty" hermit that somehow got in a hole it the rock and couldn't get out or get his arm back in the hole. That was on my first reef tank years ago. The guy I sold it to had it a couple years and it was still living in that hole doing fine. When the food floated by it looked like one of those machines where the people try to grab the dollar bills blowing around.

[geppert]

mollosk or barnacle