Super Delta Tail

Super Deltas are very similar to Halfmoons but have less than a 180 spread when flared. They are nearly a Halfmoon but not quite. Super Deltas are differentiated from Veil Tails by the fact that if you drew a line from the nose to the tip of the caudal fin on a Super Delta there would be an equal amount of fin on either side of the line, whereas on a Veil Tail there would be little tail at the top, and the majority below.

(Taken from here)