mmm, looks like it could be a B. wellsi to me. I could be wrong though. The easiest way to tell is to look at whether or not the skeleton of each polyp has a pipe like composure - if it does, it is B. merletti. However, of the polyps are flush against a rock, and lacking that "pipe" then it is a B. wellsi. I have seem some B. wellsi's are my LFS that look just like the ones in your picture (color wise).