Weirdness on a half Shell

[VR28man]

So, a small (1.5cm/ half inch), empty, half bivalve shell that came with my sand is stuck to the glass, and there’s this weird thing inside of it. Any ideas?

It was empty when introduced, so whatever it is grew in it and apparently stuck to the wall. I noticed it about two days ago. In that time, it has not moved. I have not poked it with a stick yet. ;Happy

 

[Monkeytank]

It is the operculum or trap door of a turbo snail. It's the part they use to close to protect themselves. When they die, it falls off. They are sometimes sold cleaned and polished.

 

[VR28man]

Interesting. Strangely enough, I just noticed that one of my Turbos has died.

Very very weird, and disturbing .:...

Well, i’ll take the shell and the operculum out of the tank then.....