First off is the fact that this is SUPPOSED to be a RES only pond. Had this fish been taken from my main pond there would have been other more likely possibilities. But the fact that this fish came from a pond that was stocked with RES makes the probability it has RES genes much higher. That is my first clue. I have probabilities in my corner.
Second, look at the opercular tab. Notice the orange portion of the border is relatively distinct. My GSF have a translucent orangish border but the border usually wraps around the opercular tab more of the radius and is distinctly translucent. To me this orange tab is more of a solid nature reminiscent of a RES.
Third, notice the mouth size. It is large like a GSF but the relative size of the mouth in relationship to the body height does not look large enough to be pure GSF.
Fourth, notice the green bars below the eyes. These are reminiscent of GSF bars but they lack the intensity of my pure GSF. RES often have a mottled cheek that are less bar like of the GSF but still have a pattern. The bars on this fish in coloration and shape look like some blend of what I would expect from both a GSF and a RES.
Fifth, the general body shape is similar to a GSF but to my eyes it has just a little too much height in relation to the mouth size to be pure GSF.
Sixth, the coloration with the blue-green flecks in the lower part of the body towards the tail says GSF. I do not see any of the black flecks in that area that I often see in my pure GSF.
It would be pretty easy to just call this a GSF. But the orange tab on the opercular does not look just right. The green bars do not look just right. The mouth size in relation to the vertical height of the body does not look just right. And it has some characteristics of a RES and it came from a pond full of RES that was not supposed to have any GSF in it.
That is what I see. Now I will wait to see if the experts tell me it is a GSF, LOL. I'll try to look for a good GSF picture of a fish about the same size and edit this post with it so you have a comparison.
