Weird New Coral?

[BaleKlocoon]

See the link below, i know it isn't that easy to see because it's small but I circled it in the picture. So it looks like this thing has 2 rows of teeth. It continuously opens slowly (over 20 seconds or so) and then quickly closes, and repeats over and over again. I just noticed it today. What on earth is this?

https://www.dropbox.com/s/pm7h9gpl5nuftc6/2018-04-21.jpg?dl=0

 

[ramseynb]

Looks like a small clam or some other type of bivalve.

 

[BaleKlocoon]

They attach themselves to live rock? It looks really attached to the underside of that small piece of live rock.

Anything I should do to keep it alive? Or should I care?

 

[ramseynb]

Yes, they'll attach themselves to rock. It's tough to keep them alive IIRC. You could try spot feeding it phyto but it might be a fruitless endeavor. I haven't actually gotten a live one on rock, but I've seen their shells.

 

[rhdoug]

The ones that hitched their way into my tank lasted many years without any intentional help from me.