IT'S A BOY!
Well, from my experience with those fish, it's a male.
The ovipositor of a female only shows when laying eggs and after the eggs have hatched. Also notice how pointed it's "sex organ" is. The anal fin is pointed and in some females there more rounded off. The pelvic fin shows it's long pointed ends, another way to sex Labiatus or Citrinellum or X.
Im just wondering why it doesn't display some sort of a nuchal hump?