the sepals has keel/carianata abaxial surface. Lip 3lobed, front margin of lateral lobes and mid lobe serrate/fimbriate, adaxial of lip with 3 keels, entire basal half and turned to fimbriate, fleshy white hairs on apical half. Rostelum triangular apex rounded, curved outside covered the stigma.

The flower slightly different from the true B. sinensis in China and Thailand where the species white and apical of tepals purple (in Vietnam fully purple mixed with white).