White slug??

[colenaylor]

What is this white slug that came out of my rock??

 

[salt2salt]

sponge?

 

[colenaylor]

sponge?

I identified as a Stomatella

 

[Tired]

Stomatella seems likely. If it's a flat, slug-like animal with two antennae, moves around, and has a small shell like a fingernail in its back, that's a stomatella.

 

[Alexopora]

Yeah, seems like a stomatella. If you are lucky you might have more than one and hopefully they will breed.