What is the definition of the Southern Platy?

Answer 1

The southern platyfish, commonly known as the southern platy is a species of freshwater fish in family Poecilidae of order Cyprinodontiformes. A live-bearer, it is closely related to the green swordtail and can interbreed with it. It is native to an area of North and Central America stretching from Veracruz, Mexico, to northern Belize.
The species commonly offered in pet shops is not usually a pure strain platyfish but is rather a hybrid between platyfish and green swordtail.