The morphology of pollen grains of Bournea sinensis Oliv. (A–D) and B. leiophylla (W. T. Wang) W. T. Wang (E–H) by SEM. A polar view showing pollen grain with three equatorial, colporus apertures B equatorial view showing single free, prolate pollen grain C equatorial view show apertures and granular aperture membrane D detail showing verrucate tectum with granular E polar view showing pollen grain with three equatorial, colporus apertures F equatorial view showing single free, oblate pollen grain G equatorial view show apertures and granular aperture membrane H detail showing verrucate tectum with granular.

 
 
  Part of: Chen W-H, Zhang Y-M, Guo S-W, Zhang Z-R, Chen L, Shui Y-M (2020) Reassessment of Bournea Oliver (Gesneriaceae) based on molecular and palynological evidence. In: Shui Y-M, Chen W-H, Ren M-X, Wen F, Hong X, Qiu Z-J, Wei Y-G, Kang M (Eds) Taxonomy of Gesneriaceae in China and Vietnam. PhytoKeys 157: 27-41. https://doi.org/10.3897/phytokeys.157.55254