Tuesday, June 8, 2021

[Botany • 2021] Begonia shenzhenensis (Begoniaceae, section Platycentrum) • A New Species from Guangdong, China


Begonia shenzhenensis D.K.Tian & X.Yun Wang

in Tian, Chen, Xiao, ... et Ge. 2021.

Abstract
Begonia shenzhenensis D.K.Tian & X.Yun Wang, sp. nov., a new species in Begonia sect. Platycentrum of Begoniaceae from Shenzhen of Guangdong province, China, is described and illustrated. Morphologically, it is primarily similar to B. coelocentroides in the same section but differs by its denser hairs on leaf, petiole, and pedicel, abtuse anther apex, hairy ovary, and narrower adaxial fruit wing. Based on only one small population found to date, its conservation status is assigned to Critically Endangered according to the IUCN Red List Categories and Criteria.

Keywords: Conservation status, deciduous, morphology, rhizomatous begonia, southern China, taxonomy


Figure 2. Morphology of Begonia shenzhenensis D.K.Tian & X.Yun Wang
A one of the largest plants with flowers (left corner: sections of leaf and petiole showing hairs) B staminate flowers showing in different directions C pistillate flowers, bracts (left: back view of 6-tepalled flower; right: front view of 5-tepalled flower) D inflorescence, stipules (left) and bracts (right) E fruits (top: fresh, bottom: dried) and ovary dissection (Photo by Dai-Ke Tian).

Figure 1. Plants and habitat of Begonia shenzhenensis D.K.Tian & X.Yun Wang
A plant at the earliest flowering time (6 June 2020) B plants with the dried fruits matured in the previous year C habitat showing mature plants and seedlings of the new species growing together with mosses and ferns above the rocks. (Photo by Dai-Ke Tian).

Diagnosis: The new species is most similar to Begonia coelocentroides Y.M.Shui & Z.D.Wei in the same section, Begonia Section Platycentrum (J.F.Klotzseh) A.DC. with rhizomatous habit, four tepals of staminate flowers, five tepals of pistillate flower and two-localed ovary, but clearly differs by its densely (vs. sparsely) hairy petioles and blades, hairy (vs. glabrous) ovaries, abtuse (vs. concave) anther apex, and narrower (vs. wider) adaxial fruit wing. It is also close to the small-sized individuals (before mature) of B. edulis in appearance but differs by its short and small (vs. tall and large) and non-stemmed (vs. stemmed) plants, and hairy (vs. glabrous) pedicels, flowers, and fruits (Table 1, Fig. 2).

Etymology: The specific epithet refers to the name of Shenzhen, which includes the type locality of the new species.

Distribution and habitat: The new species is only known from its type locality in Tiantou Mountain Natural Reserve of Pingshan District of Shenzhen, Guangdong Province, China (Fig. 3). It grows together mainly with mosses, ferns, and other herbs on shallow humus soil above the rocks along a small stream under forest canopy.

    


 Dai-Ke Tian, Bin Chen, Yan Xiao, Min-Min Zheng and Bin-Jie Ge. 2021. Begonia shenzhenensis, A New Species of Begoniaceae from Guangdong, China. PhytoKeys. 178: 171-177. DOI:  10.3897/phytokeys.178.66462