合柱秋海棠——越南北部喀斯特地区秋海棠科盾叶一新种（英文）

Begonia holostyla, A New Species of Peltate-leaved Begoniaceae from the Karst Region of Northern Vietnam

摘要: 描述了采自越南北部喀斯特地区秋海棠科（Begoniaceae）盾叶一新种，即合柱秋海棠（Begonia holostyla）。该新种在盾形叶和具黑色斑点的果实特征上相似于肿柄秋海棠（B. pulvinifera），但是在合生到一半的花柱和新月形的柱头方面则不同，后者花柱基部合生，柱头2次分裂成1个螺旋状的带。此外，讨论了与近缘种肿柄秋海棠的形态差异和地理联系。

Abstract: A new peltate-leaved species of the genus Begonia（Begoniaceae）,B. holostyla,was described andillustrated by photos. The new species was similar to B. pulvinifera in its peltate leaves and black dots on fruits,but differed in its styles combined to a half（vs combined at base）,lunate stigma without a spiraled band（vs 2-cleft in a spiraled band）. Additionally,the relationship of geographical distribution and morphology with thesimilar species,B. pulvinifera,was discussed.