Trying to answer my own dumb questions.....i am remiss for not having any good freshwater fish textbooks, but did find reference to origin of sunfish (and others) in CA from a Sierra Nevada natural history book i have. Probably old news for most of you, but new to me. According to this reference (and reading between the lines), Lepomis (GSF/BG/pumpkinseed were the ones mentioned), SMB, LMB, and even Gambusia were all brought west (from back east) during the "americanization" of CA...whatever that means.......when the settlers came in droves, and pushed out the mexicans and indians i guess.
So from a geologic standpoint, either the Rockies and/or the Sierra Nevada kept sunfish and Bass confined to central and eastern waters of the continent.. any western variations in these fish would have evolved in the last 200 years or so.
