I always wondered about their broken/ interrrupted / missing part lateral line.
As far as looking like other sunfish, redspotted sunfish seem to be clones of them. Catching them along side each other in Tennessee and Louisiana, the smaller ones really do that. Looking for that dorsal spot on the little bantams helped decide who was who.
They do bear a striking resemblance to banded sunfish though. At a quick glance they can resemble young dollar sunfish. But going off of color is tricky with bantams, why I nickname them the chameleon sunfish. This is in reference to badis badis.
Bantams are awesome little guys, pretty peaceful too. I once had three males and one female in a 15 gallon with just gravel and a foam filter. The female spawned with all three males, and no one got beat to near death, which would happen with any other lepomis in a proportionate sized tank.
With spending a long time with bantams, and putting aside size and personality, I really liken them to being like warmouth and green sunfish. I cannot give any concrete reasons for this, its just how I think about them.
I'm about to buy a couple from Zimmerman. I also liken them to warmouth. They both look sort of the same to me, and males of both species get the spangle on their sides and have large mouths.
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