Anyone know what this is?

I saw this for the first time early this morning around 4 am when I was looking at my tank. I dont know what it is, if it ate the snail that used to be in that shell. I know the shell was not there when I went to sleep. i tried to grab it but only got a piece of it as you can see i the last photo. It did move pretty quick, and wasnt bothered by the flashlight I was shining on it. So does anyone have an ID on this? I am off to go look at reef hitchhikers to see if I can find anything but I will be back shortly.

 

Polyclad flatworm

 

Probably Pericellis sp.

Pericelis sp. 1 Guam 403-31

 

upon doing some research I have found that to be correct, but I dont know whether to leave it be or remove the rock it was on and soak it in fw to kill it. Removing the rock is a lot of work, but I also dont want it eating any of the critters in my tank.

 

depends on how much of it you think you got. You might have killed it.

 

Thanks for the quick replies inwall. No I really doubt it is dead. I only got the small portion in the third picture, that snail shell its on in the first two photos is medium sized about 3/4" across the bottom. That thing covered the bottom and stretched to the rocks above. The piece I got was only about 1/16"

 

Right, you probably didn't kill it, since you can find them on the reef that have big chunks out of them or healed splits, and they still seem to be surviving OK. That one likely only eats molluscs, so unless you have clams or some other snails that you really value, you might be able to bide your time and try to catch it out again.

Cheers,



Don