|Begonia erythrofolia Lei Cai, D.M.He & W.G.Wang,|
in Cai, He, Huang, Dao & Wang, 2022.
红背秋海棠 || taiwania.NTU.edu.tw
Begonia erythrofolia, a new species of Begonia sect. Platycentrum (Begoniaceae) from Yunnan, China is described and illustrated. Morphologically, it is most similar to B. dielsiana and B. edulis, but differs in having broadly ovate leaves which are undivided or shallowly triangular lobed, crimson on the abaxial leaf surface, and more veins in the lamina. The new species also resembles B. subhowii in its similar leaf shape and in having erect stems when flowering, but differs in its larger leaf size, and smaller bracts and flowers.
Keyword: Begonia daweishanensis, B. dielsiana, B. edulis, B. siamensis, B. subhowii, Flora of Yunnan, new taxon, taxonomy
Begonia erythrofolia Lei Cai, D.M.He & W.G.Wang, sp. nov.
Diagnosis: The new species is mostly similar to Begonia dielsiana, B. edulis and B. subhowii in having similar leaf shape and with erect stems when flowering, but differs from B. dielsiana in having leaves undivided or with 3 very shallow lobes (vs. 5–10 lobes shallowly divided), smaller pistillate flowers (21–28 mm vs. 40–50 mm in diameter), the number of pistillate tepals (5 vs. 6, rarely 5) and the color of the lower surface of leaf blade (dark red vs. green); differs from B. edulis in being a shorter plant (16–60 cm vs. 30–150 cm) with smaller leaves (12–30 × 8–25 cm vs. 12.8–43 × 14.5–40), blade undivided or with 3 very shallow lobes (vs. 5–13 shallowly lobed, divided to ca. 1/3 of leaf length); differs from B. subhowii in being a larger plant (16–60 cm vs. 13–28 cm) with leaf blades 12–30 × 8–25 cm (vs. 4.5–9 × 10–11 cm), and smaller bracts (18–26.7 mm vs. ca. 50 mm), and the color of leaf blade (upper surface dark green, abaxially red vs. green on both sides).
Etymology: The epithet “erythrofolia” is derived from two Latin words “erythro” meaning “red colored” and “folia” meaning “leaves” referring to its leaves which are dark red on the abaxial surface.
Distribution and ecology: Begonia erythrofolia is endemic to China, currently known only from the type locality in karst region of Yunnan Province, Wenshan City, Xinjie Town, Caoguoshan Village, Qiqiutian. The species grows in humid rocky crevices under limestone forest.
Lei Cai, De-Ming He, Tai-Wen Huang, Zhi-Ling Dao and Wen-Guang Wang. 2022. Begonia erythrofolia, A New Species of Begoniaceae from southeastern Yunnan, China. Taiwania. 67(1); 110-114. DOI: 10.6165/tai.2022.67.110