taxonID	type	description	language	source
2D720B89EF535D5488FA0D47E8F10C53.taxon	description	Figs 1, 2, 3, 4 巨型秋海棠	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
2D720B89EF535D5488FA0D47E8F10C53.taxon	materials_examined	Type. China. Xizang (Tibet) Autonomous Region: Medog county (墨脱县), Beibeng town (背崩乡), Baimu Xiri river (白母西日河), forest slope of river valley or water's edge along stream, 29 ° 21 ' 9 " N, 95 ° 11 ' 21 " E, elev. 1320 m, 10 September 2020, Dai-Ke Tian, Fang Wen, Qing-Gong Mao, & Zhu Lu, TDK 4773 - A (holotype CSH! Barcode number: 0180561, ♀)	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
2D720B89EF535D5488FA0D47E8F10C53.taxon	diagnosis	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).	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
2D720B89EF535D5488FA0D47E8F10C53.taxon	description	Description. Herb perennial, evergreen, to 4 m tall, dioecious. Rhizome short, stout, nearly unbranched, reddish brown, to 12 cm thick. Stem erect, reddish brown or green, glabrous, internodes to 5 cm thick, with many longitudinally fusiform whitish spots, cross section of stem often reddish brown, nodes notably enlarged, to 7 cm thick, with unequally oval to round whitish spots, many shrubby branches on the upper part of main stem. Stipule long-triangular, light green or pinkish green, 9 - 25 x 2 - 8 mm, glabrous, margin entire, dorsal ridge pinkish, apex acuminate with arista 4 - 6 mm long. Petioles green, pink to red, glabrous, 7 - 22 cm long, 1 - 3 mm thick. Leaf blade ovate-lanceolate to lanceolate, 4 - 19 x 0.8 - 8 cm, adaxial green, muriculate to nearly glabrous, adaxial veins slightly concave; abaxial greyish green, veins usually red, convex, main veins sparsely and obliquely strigose; base obliquely cordate, margin shallowly and remotely denticulate, apex long caudate; Inflorescence dichasial cyme, axillary, short, 3 - 5 cm long, unbranched to branched once, rachis glabrous, green, pinkish green to red, base usually red-brown, 7 - 15 mm long, 1 - 1.5 mm thick, 3 - 11 male flowers or 1 - 5 female per inflorescence. Bract often caducous, pinkish green, long triangular, glabrous, ca. 6 x 3 mm, apex acuminate; bracteoles smaller. Staminate flower: pedicel glabrous, white, whitish or pinkish green, 10 - 14 mm long, ca. 1 mm thick; corolla 18 - 24 mm in diameter; tepals 4, subequal, glabrous, outer 2, obovate, 9 - 14 x 6 - 9 mm, apex obtuse, adaxially white and middle-upper part abaxially pink, or pure white for some individuals, longitudinal veins unapparent; inner 2, pure white, obovate to obovate-lanceolate, 8 - 13 x 5 - 7 mm, apex obtuse; androecium nearly actinomorphic, ca. 5 mm long, 6 - 7 mm in diam; stamens 48 - 60, filaments free, 1 - 2 mm long; anther yellow, 2 - 3 mm long, apex obtuse or nearly so. Pistillate flower: pedicel white or green-white, 6 - 12 mm long, 0.8 - 1 mm thick; corolla 20 - 25 mm, tepals 6, rarely 4, glabrous, outer 3 (rarely 2), obovate or long obovate, thick and rigid, 12 - 18 x 7 - 10 mm, adaxial surface nearly white, distinctly concave, abaxially pink on middle-upper part, inner 3 (rarely 2), obovate-lanceolate to oblanceolate or long elliptical, slightly narrower than outer tepals, 10 - 19 x 6 - 8 mm, white, glabrous, apex obtuse; styles + stigmas 5 mm long, 7 - 8 mm wide; styles 3, free; stigmas yellow, nearly U-shaped, each side spirally twisted 1.5 circles; ovary pink or green, with white convex spots; placentation axile, 3 - loculed, each placenta 2 - branched. Peduncle green to pinkish green, glabrous, 8 - 12 mm long, ca. 1 mm thick. Fruit red, pink or green, glabrous, triangular-gyroscopic, 8 - 11 x 1 - 12 mm wide, concave between two placentas, wingless to occasionally short ridged, apex with beak 3 - 4 mm long. Flowering Jun. - Oct., fruiting Jul. - Dec.	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
2D720B89EF535D5488FA0D47E8F10C53.taxon	distribution	Distribution and habitat. Currently known from at least two localities in Medog, southern Xizang (Tibet), China (Fig. 5). It grows on the slopes under forest along streams, elevation 450 - 1400 m.	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
2D720B89EF535D5488FA0D47E8F10C53.taxon	etymology	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.	en	Tian, Dai-Ke, Wang, Wen-Guang, Dong, Li-Na, Xiao, Yan, Zheng, Min-Min, Ge, Bin-Jie (2021): A new species (Begonia giganticaulis) of Begoniaceae from southern Xizang (Tibet) of China. PhytoKeys 187: 189-205, DOI: http://dx.doi.org/10.3897/phytokeys.187.75854, URL: http://dx.doi.org/10.3897/phytokeys.187.75854
