Cool link, I'm bookmarking it. I want some of those macros.

Sure looks like Jania rubens. Might have some mesophyllum growing on it as well, I just thought it was a weird plating coralline.

So Jania rubens is great in makeup and skin moisturizers, but considered 'biofoul' to shellfish farmers... its is rare, but abundant... and found everywhere in the world at any depth, depending on which site you read. Gotta love random google research.