Saturday, September 19, 2015

[Botany • 2015] Begonia difformis • A New Species (Sect. Platycentrum, Begoniaceae) segregated from B. palmata D. Don. distributed in Yunnan, China



Begonia difformis
  (Irmsch.) W.C. Leong, C.I Peng & K.F Chung
FIGURE 1. Begonia difformis (A, B, E, F) and B. palmata (C, D).
A. Habitat. B. Habit. C. Male and female flowers. D, E. Abaxial surface of staminate flower, note the red-m on tepals of B. difformis (E). F. Pistillate flower.
Scale bars A–C. 4 cm. D–F. 1 cm. || DOI: 10.11646/phytotaxa.227.1.9

Abstract
Begonia palmata D. Don is one of the most widely distributed and morphologically variable species of Asian Begoniaceae. Examinations of its morphological variation indicate that two of its seven varieties, B. palmata var. difformis and B. palmata var. crassisetulosa, both distributed in the Gaoligong Mountain areas of Yunnan, China are indistinguishable and yet distinct from other varieties. Phylogenetic analyses using ITS DNA sequences further reveals that samples identifiable to these two varieties are also distantly related to samples of typical B. palmata. Based on these observations, we combine and elevate these two varieties to the status of species, Begonia difformis (Irmsch.) W.C. Leong, C.I Peng & K.F Chung, comb. & stat. nov..

Key Words: Begonia palmata var. crassisetulosa, flora of China, ITS, Yunnan


FIGURE 1. Begonia difformis (A, B, E, F) and B. palmata (C, D).
A. Habitat. B. Habit. C. Male and female flowers. D, E. Abaxial surface of staminate flower, note the red-m on tepals of B. difformis (E). F. Pistillate flower.
Scale bars A–C. 4 cm. D–F. 1 cm. || DOI: 10.11646/phytotaxa.227.1.9

Taxonomic treatment

Begonia difformis (Irmsch.) W.C. Leong, C.I Peng & K.F Chung, comb. & stat. nov. (Fig. 1)
Chinese name: 刺毛紅孩兒.

Basionym:— Begonia laciniata Roxb. subsp. diffromis Irmsch. (1939: 531).

Distribution & habitat:— Begonia difformis occurs at the elevation at 1500–3200 m in western and southwestern Yunnan (Fig. 3), commonly found on sandstone rock crevices of the moist environments by streams or on mountain slopes under evergreen broadleaved forests or coniferous forests.

Phenology:—Flowering June–October; Fruiting August–November.




Wai-Chao LEONG, Tao DENG, Hang SUN, Ching-I PENG and Kuo-Fang CHUNG. 2015. Begonia difformis comb. & stat. nov. (Sect. Platycentrum, Begoniaceae), A New Species
segregated from B. palmata D. Don. Phytotaxa. 227(1): 83–91. DOI: 10.11646/phytotaxa.227.1.9

No comments:

Post a Comment