Hmmm...what is this?

[D_Foster]

Can anyone tell me what this is? Is it a piece of shell, is it an animal, or alien? We just happened to see it tonight. We have various snails, shrimps, and a few fish. If it hitchhiked it's been in here a long while as the last thing we got was 5 bumblebee snails a week ago and before that it's been 6 or months since we added anything else new. It's currently in tank water on my counter. Thanks all!

 

[Sisterlimonpot]

It's the operculum of a snail shell.

 

[Crabs McJones]

Looks like a snail door. the little flapper door they close when they go into their shell

 

[D_Foster]

It's the operculum of a snail shell.

Thank you! I thought it was something like that but I wasn't sure!