"I recently wrote up some of my frustrations identifying this group on my own web site at http://www.underwaterkwaj.com/nudi/nudi.htm. Yes, I think I would call this Phyllidia carlsonhoffi, although I have seen specimens of Phyllidia madangensis that look virtually identical dorsally. The only way to tell them apart sometimes is to look for a dark line running along the center of the bottom of the foot, present in Phyllidia carlsonhoffi and absent in Phyllidia madangensis."