What are these fish?

We recently caught some fish in a lake in Southern Georgia and have been trying to determine what they are. The closest we can figure is possibly Platy fish, but it doesn't seem like Platy fish are originally from Georgia. Can you figure out what these fish are?

	Drawing This shows the fin and eye markings better than the pictures with the camera could (sorry it looks upside down -- it's supposed to be right side up).
	Photograph Nice sharp picture
	Photograph I just included this one because it looks creepy -- my boyfriend managed to take a picture of the fish right as its mouth was open really wide (it must do this so fast, I never notice it normally).
	Photograph Look at the tail and you can see the markings I drew in the picture
	Photograph Two fish (this shows their real color much better).