Six new species of Begonia (Begoniaceae) from limestone areas in Northern Vietnam.

Ching-I Peng,Che-Wei Lin,Hsun-An Yang,Hieu Quang Nguyen,Yoshiko Kono

doi:10.1186/s40529-015-0089-3

Abstract

BackgroundSpecies of Begonia are richly represented in limestone karst areas across the Sino-Vietnamese border. More than one hundred species were known, many of which were documented recently.ResultsIn continuation of our systematic studies of Asian Begonia, we report six species of Begonia that are unknown to science, namely B. caobangensis [sect. Platycentrum], B. circularis, B. melanobullata, B. langsonensis, B.locii and B. montaniformis [sect. Coelocentrum] from Northern Vietnam. Diagnostic features that separate them from morphologically allied species are provided. Somatic chromosome numbers were determined, which supports their placement in the respective sections. Foliar SEM microphotographs were taken and described.ConclusionA careful study of the literature, herbarium specimens and living plants, both in the wild and in cultivation in the experimental greenhouse, supports the recognition of the six new species, which are described and illustrated.Electronic supplementary materialThe online version of this article (doi:10.1186/s40529-015-0089-3) contains supplementary material, which is available to authorized users.

Highlights

Species of Begonia are richly represented in limestone karst areas across the Sino-Vietnamese border
Coelocentrum is richly represented in limestone karst areas across the Sino-Vietnamese border region, comprising more than 60 species (Peng et al 2014a, Chung et al 2014)
Chromosome preparations Somatic chromosomes were studied for plants of Begonia caobangensis (Peng 23895, HAST), B. circularis (Peng 22610, HAST), B. melanobullata (Peng 22609, HAST), B. langsonensis (Peng 21946, HAST), B. locii (Peng 21943, HAST) and B. montaniformis (Peng 24609, 24610, 24613, HAST) using root tips

Summary

Introduction

Species of Begonia are richly represented in limestone karst areas across the Sino-Vietnamese border. Coelocentrum is richly represented in limestone karst areas across the Sino-Vietnamese border region, comprising more than 60 species (Peng et al 2014a, Chung et al 2014). Coelocentrum were discovered in the past decade (Chung et al, 2014; Peng et al 2013, 2014a), mostly from southern China. Averyanov and Nguyen (2012) documented ten new species of Begonia from Vietnam and one new species from Laos. They estimated the total actual number of Begonia species in eastern Indochina to be 180–200 species. Coelocentrum from Vietnam, some with very handsome maculation pattern and/or attractive leaf texture and an unusual new species of sect.

Methods

Results

Conclusion