ID this bivalve?

[Sonam]

Hello All,

Relatively new to the hobby (over a year now but a constant learning curve).

Found this critter on a rock in our refugium. It wasn't purchased, but somehow grew in there.

Would love to know what it is if anyone knows.

Thank you for your time...

 

[ebushrow]

Scallop

 

[Sonam]

Thank you!