What’s this living on hermit shell

[andrewkg]

Seems like some kind of mollusk that opens, any ideas? Check video something Black looks like tongue comes out

 

[susan ingram]

WOW!!! I have no clue... maybe the Alien come back as an aquatic??? Seriously.. let's bump it and find out!

 

[stanleo]

First thing that came to mind is a limpet.

 

[najer]

As above.

 

[dhanking]

Limpet. I would remove it because it probably creates extra work for your crab