Hitchhiker on Cerith Snail?

[KellyGee]

Hey guys,

I’ve had this Cerith snail since October - I thought I’d just gotten an ugly boy but over the last month or so his “protrusion” has gotten bigger, and today I just saw that it has a mantle/mouth that is opening? Could anyone help me out with an ID?
Thanks all and happy reefing!

 

[Sharkbait19]

Looks like some sort of bivalve, nothing to worry about (unless the snail has trouble moving).

 

[KellyGee]

Looks like some sort of bivalve, nothing to worry about (unless the snail has trouble moving).

Thanks Sharkbait! Little guy doesn’t seem to be having any issues, it’s more that I’m just fascinated with hitchhikers!
I guess the little girl inside me was hoping it was going to be some fantastical looking clam or scallop….