I couldn't get that photo to enlarge on my cell phone but am certain it is a female. Day geckos can be funny sometimes as far as being able to tell and if you aren't checking them(Phelsuma) on a regular basis it can be even more difficult to know for sure. I have never seen a male day gecko eat a dud egg either. That is something females will do to regain the nutrients and calcium. Females will eat each other's eggs too. Some people don't recommend keeping certain species in groups because sometimes the females will eat each other's good eggs. Anyhow, I'm done beating this horse. If you want to believe you have a pair go for it. Maybe I'm wrong...