The picture is really hard to tell. I can't get a good read on this one. With the light color and being female you could see the overlies clearly. but Petco has listed this as a male and I would say they are not off the mark. It would be their breeder who sexes the fish not the stores or corp. Some males will show an egg spot at a very early age and loose it as they mature. I did not see any reason from the photo to disbelieve the breeder or the store. I would be safe to say you have a male.