We toss around the term intergrade a lot, and I don't dispute that, but could another possibility exist? It used to be common to hear authorities describe two sub species of CNBG....macrochirus purpurescens, and macrochirus mystacalis.
Mystacalis was thought of as a Florida strain, while purpurescens was described as indigenous to some southern Atlantic coast states. Now, many consider them to be one and the same...maybe not, at least for appearance sake.
I know there are threads here somewhere that contain info.... Maybe Travis put something up?
Tony, there's probably some truth to all that.
Basically, I guess this is what I'm after. With vertical stripes of course.