Feather Duster?

[rdahlke1105]

This thing looks kinda like a feather duster, if a snail gets too close it retracts into the sand. Though I hadn't heard of them being in the sand.

 

[ErinCahir]

I have a couple in my sand. They're very pretty... much bigger than the ones on the rocks.

 

[Piratefish]

I have them in my sand bed as well. I like them.

 

[Aquatic]

Sounds like a nice find you have there.