A new species of Begonia (Begoniaceae) from Guangxi, China

Abstract

Begonia gigabracteata H.Z. Li & H. Ma sp. nov. (Begonia section Diploclinium, Begoniaceae) is described and illustrated from North Guangxi Zhuang Autonomous Region, south-west China. Its chromosome number (2 n = 30) and pollen and seed micromorphology are reported. This species grows in ravines on damp or slightly moist limestone. It is morphologically similar to B. summoglabra T.T. Yü (section Reichenheimia) and B. labordei H. Lél. (section Diploclinium). However, it differs by its sparse glandular hairs, number of perianth segments, colour of venation on the abaxial blade, and unique heteromorphous bracts. A line drawing and plate of B. gigabracteata and a photograph of the type of B. summoglabra are presented as an aid to identification. © 2008 The Linnean Society of London.