 |
| Begonia giganticaulis D.K.Tian & W.G.Wang, in Tian, Wang, Dong, ... et Ge, 2021. |
Abstract
Begonia giganticaulis, a huge new species in Begonia sect. 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.
Keywords: Conservation status, molecular evidence, morphology, southern Tibet, taxonomy
Begonia giganticaulis D.K.Tian & W.G.Wang, sp. nov.
Diagnosis The new species is mostly similar to B. longifolia and B. acetosella, but clearly differs from the former mainly by its dioecious (vs. monoecious), taller (to 4 m vs. less than 2 m) plants, longer (vs. shorter) inflorescence, and unique shape of fruits, and differs from the latter mainly by its taller (to 4 m vs. less than 2 m) plants, late and longer (Jun. to Oct. vs. Mar. to Apr.) flowering time, longer (6–20 mm vs. 5–12 mm) pedicel, 6 (vs. 4) tepals of pistillate flower and 3 (vs. 4)-loculed ovary (Table 3, Fig. 3).
Etymology: The specific epithet refers to the huge (very tall and thick stem) plant size of the new species, which is the tallest begonia in Asia.
Dai-Ke Tian, Wen-Guang Wang, Li-Na Dong, Yan Xiao, Min-Min Zheng and Bin-Jie Ge. 2021. A New Species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys. 187: 189-205. DOI: 10.3897/phytokeys.187.75854
