I thought his toakiensis and the one you identified as natalensis looked similar. My powers of observation are improving!
Weeds are flowers too, once you get to know them - A.A. Milne
I think I'm addicted
Here's my two cents on IDing these. I'm not sure if that helps or obscures the matter. Most of my IDing skill of these plants comes from Schnell's 2002 book, which I used extensively when living in the SE. I certainly agree with your implication that there may be fertile hybrids.
Originally Posted by hcarlton
Well, now I need to relabel those plants and contact the person I got them from to say they were mislabeled.