An independent Taiwanese lineage of powdery mildew on the endemic host species Koelreuteria henryi.

In Erysiphe on Koelreuteria hosts, speciation of plant parasitic fungi seems to be correlated with disjunct host and geographic distribution possibly shaped by extinction of potential host species which are known only as fossils. Two of the three extant East Asian species of Koelreuteria are now known as hosts of specific Erysiphe species. We may predict a further not yet discovered Erysiphe species on the third East Asian species, K. bipinnata, in South and Southwest China. In the speciation in Sawadaea, the extinction events in Koelreuteria can be excluded from being involved.