Mystery Critter - what is it?

[NeedBiggerTank]

Was spying on my tank with a flashlight the other night, as I often do, and on the back side of the tank, saw the "foot" of what I thought was a Limpet (I have several - Carabbean striped keyhole limpets). Only this didn't look quite right - at first I thought it was sitting on top of a colony of coralline algae, but then realized that the translucent "skirt" was attached to this critter.

Unfortunately, it is nearly impossible to see what the "top" looks like, as the only way to look at it on the back glass is from behind (looking at the bottom of the foot) or from the side (there are rocks directly in front of it) . The foot is oval and the mouth is round - from underneath, it looks similar to a snail or limpet - only the foot expands outward into a transluscent "skirt". This skirt is about half as wide as the foot and flat (not frilly or curled). From what little I can see of what the top looks like, it has some sort of shell or plates that are pointed in the center - kind of like my limpets.

Does anyone have a clue what this is?

 

[CAMAKAZY]

I used to have a keyhole limpet like the second one in link. I'm not sure what it ate, but lived around two years.

http://www.seaslugforum.net/showall/keyhole

 

[NeedBiggerTank]

My first thought was that it was a different type of limpet than the others I have - I was just stumped by the extension of the foot outward. From the side it kinda looks like a huge pimple sitting on flesh colored transluscent skin. LOL

I wish I could see it straight-on from the front/top. It seems to stay on the glass - in a fairly small area behind the rocks.

 

[CAMAKAZY]

I also had regular keyhole limpets the same time I had the one with the skirt. All where hitchhikers, but all lived about 2 years. Maybe the one with the skirt is like the queen in aliens. :fun5:

 

[NeedBiggerTank]

LOL - Well, it wouldn't be the first "alien" that appeared mysteriously out of my live rock. We've had social tunicates, mini feather duster worms, crabs, several different types of star fish, anemonies, filter feeding cucumbers, a mantis shrimp and probably lots of things I don't know that we have!

 

[SNAKEMANVET]

Might be a stomatella,they have a small shell and their foot extends.Post a pic if possible.