I found two huge climbing phyllostegia vines in Kipuka Ahiu along Powerline Road on the Saddle. The stems were over an inch diameter at the base, and the vines were many branched and climbing high into the trees and tree ferns overhead. Unfortunately the plants were long done flowering when I found them in July. The largest leaves were about 3-4 inches by 2 inches, glabrous on top and lightly pubescent on the underside (vines only?). The nutlets appeared to be very tiny and brown, and may not be good.
I'm not sure which species this is. Perhaps a kind of phyllostegia ambigua?