Those certainly look like greengills to me.
I usually catch pumpkingreens, or greenseeds if you'd rather, during the summer. If I can get some shots of those I will post them. Very pretty fish. Sad thing, the one pond they used to be found in pretty regular is nearly dried up. Some of it is drought, I think most of its irrigation nearby. Other ponds a mile or so away are fine in level.
Pumpkingreens are one of the most common hybrids around this area. They are also very aggressive and bite readily. This transfers to the aquarium. Think greens are good at dominating a tank, try one of these guys. They eat anything, had one in biology class, it ate most items from peoples lunch. Gummi worms and baloney sandwich pieces were it's favorite. I gave him the name tank, since he became huge and bulky after killing off all competition and eating all that junk food. The incredible bulk was a second choice for a name.