A new species (Begoniagiganticaulis) of Begoniaceae from southern Xizang (Tibet) of China.

Dai-Ke Tian,Min-Min Zheng,Yan Xiao,Li-Na Dong,Wen-Guang Wang,Bin-Jie Ge

doi:10.3897/phytokeys.187.75854

Abstract

Begoniagiganticaulis, a huge new species in Begoniasect.Platycentrum of Begoniaceae from southern Xizang (Tibet) of China, is described. Morphologically, it is mostly similar to B.longifolia and B.acetosella, but clearly differs from the former mainly by its dioecious and taller plants, sparse hairs on abaxial veins, longer inflorescence, unique shape of fruits, and differs from the latter mainly by its late and longer flowering time, 6-tepals of female flower and 3-loculed ovary. The phylogenetic analyses also support the separation of the new species from other taxa. Based on the current data, its conservation status is assigned to Endangered (B2a) according to the IUCN Red List Categories and Criteria.

Highlights

Zangnan of China is located to the south of the Himalayas, including most parts of Cona, Lhünzê, Mêdog and Zayü counties, and some smaller parts of Nang and Mainling counties (Liu 2019)
Begonia limprichtii Irmsch. (Irmscher 1922) was newly reported by Borah et al (2021a) in southern Tibet, but this record is likely based on a wrong identification and further study is needed
We described Begonia giganticaulis D.K.Tian & W.G.Wang sp. nov. from Mêdog, a new species of huge plant size, which is morphologically similar to both B. longifolia Blume (Blume 1827) and B. acetosella Craib (Craib 1912)

Summary

Introduction

Zangnan (southern Tibet) of China is located to the south of the Himalayas, including most parts of Cona, Lhünzê, Mêdog and Zayü counties, and some smaller parts of Nang and Mainling counties (Liu 2019). From Mêdog, a new species of huge plant size, which is morphologically similar to both B. longifolia Blume (Blume 1827) and B. acetosella Craib (Craib 1912). The field surveys were conducted on habitat, distribution, population size, morphology and specimen collection of the new species.

Results

Conclusion