The angel in the banner at the top of this page has a deformed dorsal fin, too many spines in it. The photo was taken by Ronny about 10 years ago.
Cheers Terry
Don't know where you access your info on diagnostic imperatives for angels Terry, but I have to disagree with your statement that "there are too many spines in the dorsal fin". It is possible that some are more elongated than usual, but this is by no means "deformed". I have searched several hundred photos of angels; both wild-caught and aquarium strains, and there are many that look very similar to the banner photo. Schultz, in his original description indicates a dorsal ray count of 23-29 for P scalare. If anything, the count in the banner photo would appear reduced, but that is just guessing, which I feel is what you are doing.
Syd.