ID request ... algae? coralline? I have no idea

[Quartapound]

Does anyone know what this is? it's been growing on this small piece of liverock VERY slowly... doesn't seem to have any "depth", it looks paper thin. it has a striking pattern in it, beautiful deep red colour...

Any ideas? this is the best pic I have so far

 

[kschweer]

From the picture I think it could be a mushroom. A better picture would definitely help with an ID.

 

[akitareefer]

Hard to see. Possibly a type of coralline or sponge

 

[Lionfish Lair]

Does it look like this? It's in my tank.