There are at least three forms of ningmingensis, and I believe this one is the type locality. It slightly resembles B. arachnoidea in the leaf patterns. It is a slower growing species, and of the three ningmingensis types, which all display somewhat drastically different growth habits, this is the one in the middle in terms of difficulty and growth rate. The dark form is the fastest growing of the three, with var. bella being the more difficult and slow growing in my experience. The leaves on the Vietnam ningmingensis reach about 4-5″ typically, and the whole plant is no larger than 8″.
The Begonia in the middle of this bin, with the distinctive palmate white markings is ningmingensis ‘vietnam’.
And the flower,