Your begonia is clearly rhizomatous, as I gather in checking google B. barkeri is. I'm not familiar with barkeri, which isn't surprising considering the thousands of begonia species and hybrids! Looks to be a form or hybrid of B. ricinifolia--those soft 'prickles' on the stem and forming a collar at the base of the leaf where it joins the petiole indicate that--but I don't know which one. That might help you find it though. They all take about the same care, which you seem to be providing it already--moist but never soggy potting mix, bright light but little or no direct sun, light fertilizer.

Thank you for the lead.... I'll see what I can find :D

this most certainly has B. ricinifolia in its heritage. there are a few cultivars it might be...my guesses are either B. Fischer's ricinifolia or B. 'Immense,' these are pretty old fashioned and the only place i've ever seen 'Fischer's ricinifolia' pictures is in an old Begonia book by Bernice Brilmeyer. you have a beautiful begonia anyway.

-ming

Thank you... those were two that I ended up narrowing it down to. Apparently a local library has a book called Exotica which has every plant ever known (to the date printed)... I hope to get over there next week to see what I can find in it :D

i don't think Exotica or Tropica (Graf) list too many hybrids.

-ming

:( Well, it'll be fun to flip thru either way :D