99% of female livebearers have a gravid spot, even when not pregnant.
I would issolate her to another tank though, she doesn't look too good to me, scales missing, curved spine. the scales look like they have the start of fungus
i will look into getting her into another tank, update on her spine, it looks bent in the picture however its straight in the tank. shes very active, eating well. and social with other females in the tank