Begonia ehuangzhangensis (sect. Diploclinium, Begoniaceae), a new species from Guangdong, China Author Ding, Qiao-Ling Author Zhao, Wan-Yi Author Yin, Qian-Yi Author Ye, Hua-Gu lsslwb@mail.sysu.edu.cn Author Song, Han-Zhang Author Liao, Wen-Bo lsslwb@mail.sysu.edu.cn text Phytotaxa 2018 2018-12-07 381 1 107 115 http://dx.doi.org/10.11646/phytotaxa.381.1.14 journal article 10.11646/phytotaxa.381.1.14 1179-3163 13726064 Begonia ehuangzhangensis Q.L. Ding, W.Y. Zhao & W.B. Liao , sp. nov. ( Figs. 2 & 3 ). Diagnosis: — Begonia ehuangzhangensis is most similar to B. fimbristipula Hance (1883: 202) in tuber shape, placentation type , and leaf number, but significantly differs by petiole and blade glabrous ( vs . hairy), female flower 2 tepals ( vs . 3 tepals), and later flowering period (August vs . May). Begonia ehuangzhangensis also resembles B. rongjiangensis T.C. Ku in Wu & Ku (1995: 279) but distinguished from the latter in having glabrous outer tepals of male flower, glabrous ovary, glabrous and persistent bracts, U-shaped stigmas, and solitary leaf per tuber. Comparison of the above three species is provided in Table 1 . FIGURE 1. Distribution of Begonia ehuangzhangensis (▲) in Guangdong province of China. Type :— CHINA . Guangdong :Yangchun City, Bajia Town,Ehuangzhang Nature Reserve,elev. 704m , 21°52’26.88” N , 111°25’20.51” E , on wet, mossy rock slope at sides of valley, along the stream, 5 August 2017 , H . G . Ye, W . Y . Zhao, Z . C . Liu, YC-2017-13 ( Holotype SYS !, isotypes SYS !, IBSC !). Description :— Herb monoecious, deciduous perennial, epipetreous with tubers; tuber irregular globose, 6–8 mm in diameter, single or two connected. Leaf solitary per tuber, basal; stipule caducous; petiole green or slightly reddish, 3.5–8.5 cm long, 1.5–3 mm in diameter, glabrous; blade slightly oblique, ovate, 4–12 × 2.5–6.5 cm , chartaceous, glabrous, adaxial surface green, abaxial surface reddish, base slightly cordate, margin biserrate, apex acute or cuspidate; venation palmate, green, usually 7-veined, raised on abaxial surface. Inflorescence 1 or 2, arising from the tuber, dichasium, 4.5–12.5 cm tall, glabrous; peduncles green or reddish, 4.5–9 cm long and 1–3 mm in diameter; bracts reddish, triangular, margin serrate, ca. 2 × 1 mm , glabrous, persistent, 1 or 2-paired at the base of each peduncle; bracteoles reddish, tridentate or slight tridentate at apex, margin sparsely glandular ciliate, remotely serrulate at middle and base, ca. 3 × 1 mm , paired at each pedicel node. Staminate flower : pedicel glabrous, 1–2.2 cm long; tepals 4, pale-pink, glabrous, outer 2 ovate to broad ovate, 4–6 × 3–5 mm , inner 2 narrowly obovate, 4–6 × 1–1.5 mm ; filaments fused to about 1 mm at base; anther hemispherical, yellow, about 0.5 mm long. Pistillate flower : pedicel glabrous, 1–1.5 cm long; tepals 2, pale-pink, glabrous, broadly obovate, 3–3.5 × 3.5–4 mm ; ovary oblong, reddish, glabrous; placentation axile, bilamellated; styles 3, fused at base; stigma U-shaped, papillate. Capsule nodding, ca. 8 × 7 mm , unequally 3-winged, abaxial wing oblate-triangular, ca. 4 × 5 mm , apex acute, lateral wings smaller, lunate, about 1 mm in width; seeds many, brown, ellipsoid. TABLE 1. Morphological comparison of Begonia ehuangzhangensis , B. fimbristipula , B. rongjiangensis , and B. labordei .

B. ehuangzhangensis	B. fimbristipula	B. rongjiangensis	B. labordei
Leaf number	solitary	solitary	2–5	solitary
Leaf size	petiole 3.5–8.5 cm long; blade 4–12 cm × 2.5–6.5 cm	petiole 3–11.5 cm long; blade 6–13 × 4.8–8.5 cm	petiole 4–9.5 cm long; blade 8.5–11 × 5.5–9.5 cm	petiole 6.5–24.6 cm long; blade 10–25 × 6–22 cm
Leaf indumentum	petiole glabrous; blade glabrous	petiole villous; blade abaxially hairy, adaxially sparsely pubescent	petiole glabrous; blade glabrous	petiole glabrous or hairy on upper part; blade subglabrous to abaxially sparsely hirsute, adaxially hispidulous
Leaf margin	biserrate	denticulate	shallowly serrate, sometimes biserrate	unequally serrate
Inflorescence	4.5–12.5 cm tall, glabrous	6–18 cm tall, glabrous	15–22 cm tall, glabrous	2–6.5 cm tall, glabrous
Bracts	persistent, glabrous	base part caducous, glabrous	caducous, villous	base part caducous, glabrous
♂ tepals	4, glabrous, outer two 4–6 × 3–5 mm, inner two 4–6 mm × 1–1.5 mm	4, glabrous, outer two 8–13 × 8–10 mm, inner two 7–12.5 × 4–5 mm	4, outer two 6–8 × 6–7 mm, abaxially villous, inner two 6–8 × 1–2 mm	4, outer two 10 × 6–7 mm, glabrous or abaxially hairy, inner two 7 × 5 mm
♀ tepals	2, glabrous, 3–3.5 mm× 3.5–4 mm	3, glabrous, outer two 6–8 × 9–11 mm, inner one 6.1–9.2 × 2.8–4.2 mm	2, glabrous, 7–8 × 6–7 mm	3 (or 4), outer two 9–10 × 6 mm, glabrous or abaxially hairy, inner 1 (or 2) 6–7 × 2–3 mm
Ovary	glabrous	glabrous	hairy	glabrous or hairy
Stigma	U-shaped	U-shaped	globose	3, 2-cleft or U-shaped, spiraled or not
Capsule	ca. 8 × 7 mm	ca. 11 × 7–8 mm	unknown	ca. 10 × 6–7 mm
Phenology	Flowering August	Flowering May	Flowering August	Flowering August

Additional specimens examined ( paratypes ) :— CHINA . Guangdong Province , Yangchun County , Bajia Town , Ehuangzhang Nature Reserve , elev. 700 m , 21°52’26” N , 111°25’20” E , 5 August 2017 , H . G . Ye, W . Y . Zhao, Z . C . Liu,YC-2017-40 ( SYS !) ; ibid., 9 November 2017 , W . Y . Zhao, F . Ye, J . W . Pan, YC-2017-49 ( SYS !) ; ibid., elev. 720 m , 21°51’47” N , 111°25’29” E , 5 August 2018 , Q . L . Ding, W . Y . Zhao, Q . Y . Yin, Y . R . Liu, YC-2018-16 ( SYS !) . Distribution and habit :—The new species is currently known only from the Ehuangzhang Nature Reserve ( Fig. 1 ) and grows on moist rocky slope at sides of valley, along the stream in broad-leaved mixed forests at about 700 m in elevation. Phenology :—Flowering August to September, fruiting September to October. Etymology :—The specific epithet is derived from the type locality, Ehuangzhang Nature Reserve of Guangdong Province , China .Although several endemic species from Ehuangzhang Nature Reserve were named after the Yangchun city ( Kiu 1995 , Ye et al . 2003 , 2006 , Wang et al . 2005 ), the authors wish to emphasize the unique geographical features of Ehuangzhang Nature Reserve, thus to name this new species after this nature reserve.