OK.....IME When a JD's spotting on the gill plate is circular it is male. When the blotches look more like a bean...Female...Yours looks to have the circles as apposed to the beans..lol Snapped a couple pics for you. First is female, second is male...Sorry for the bad pics, but I snapped them in a hurry and only took 4 pics total...HTH...
Look not just at the spangling (which says female) but at the more stout body shape and the fins.
I don't think sexing by the shape of the coloration is a good way to do it, you need to look at the area the coloration covers. With the fish in question the color goes all the way to the edge of the gill plate, something that doesn't happen in males. The other photos posted show this as well. The females blue goes to the edge, while the males does not.
Here are some shots of my old breeding pair. Don't just look at the color, look at the fin and body shape.