1 | Leaves palmately compound |
1' | Leaves simple, sometimes lobed or pinnatisect |
2 | Robust plants up to c.100 cm in height; moderately to densely hairy on all above-ground vegetative parts; female inflorescence 2-flowered; pedicel of the fruits long (16-19 mm); wings of the fruits unequal with one wing much larger than the other two Begonia insueta in Edinburgh J. Bot. 68(2): 230. 2011 |
2' | Small, delicate plants, to c.40 cm in height; glabrous except for microscopic glandular hairs; female flowers solitary; pedicels of the fruits very short (c.1 mm); wings of the fruits subequal Begonia rachmatii in Edinburgh J. Bot. 61(2-3): 101. 2005 |
3 | Leaves pinnatisect to bipinnatisect Begonia humilicaulis in Bot. Jahrb. Syst. 50(4): 356. 1914 |
3' | Leaves entire or when lobed then maximally halfway to the midrib |
4 | Leaves peltate (some leaves, especially the subtending leaves of the inflorescences, sometimes with basifixed laminas) |
4' | Leaf laminas basifixed |
5 | Ovaries and fruits wingless, fruits > 4 cm long Begonia vermeulenii in Edinburgh J. Bot. 68(2): 248. 2011 |
5' | Ovaries and fruits with well-developed wings, fruits < 3 cm long |
6 | Leaf lamina c. 7-11 cm wide; male inflorescence composed of compressed monochasial partial inflorescences; tepals of male flowers 11-17 mm broad; androecium of more than 60 stamens Begonia comestibilis in Edinburgh J. Bot. 68(2): 226. 2011 |
6' | Leaf lamina c. 3-7 cm; male inflorescences dichasial or with dichasial branching in the basal part and monochasial branching in the distal part, with well developed internodes; androecium of c. 25-30 stamens Begonia varipeltata in Edinburgh J. Bot. 65(3): 370. 2006 |
7 | Female inflorescences or partial infloresences 1- or 2-flowered, separated from the male inflorescences or inflorescence parts by at least one internode |
7' | Female and male flowers occurring together in mixed cymose inflorescences with > 2 female flowers |
8 | Plants with swollen underground organs consisting of one to several tuberous units up to 3.1 cm long and 1.1 cm thick; filaments of the stamens fused into a short filament column Begonia siccacaudata in Blumea 45(2): 400. 2000 |
8' | Plants without tuberous underground organs; filaments free or only fused at the very base |
9 | Plants creeping or decumbent, < 25 cm in height |
9' | Plants erect, or if decumbent or arching > 25 cm in height |
10 | Ab- and adaxial leaf surfaces with long, erect trichomes; plant rhizomatous Begonia mendumiae in Edinburgh J. Bot. 63(2-3): 196. 2006 |
10' | Ab- and axial leaf surafce glabrous, or abaxial surface with sparse strigose indumentum; plants creeping or decumbent, not rhizomatous |
11 | Leaf margin unevenly dentate; pedicels of fruits > 10 mm Begonia heteroclinis in Meded. Lands Plantentuin 19: 484. 1898 |
11' | Leaf margin shallowly lobed; pedicels of fruits < 10 mm |
12 | Stems and nerves of abaxial leaf surface with microscopic glandular hairs and macroscopic trichomes; SE Arm of Sulawesi Begonia flacca in Webbia 9: 486. 1954 |
12' | Stems and leaves glabrous except for microscopic glandular hairs; N arm of Sulawesi Begonia gemella in Phytologia 52(7): 443. 1983 |
13 | Leaf margin distantly dentate and unevenly repand Begonia sarasinorum in Bot. Jahrb. Syst. 50(4): 349. 1913 |
13' | Leaf margin serrate to biserrate or dentate to bidentate, sometimes shallowly lobed (up to c.50% of the lamina width) |
14 | Petioles short (up to 10 mm), leaves long and narrow (c. 5-12 x 1.5-3.1 cm, length/width ratio > 3:1) Begonia cuneatifolia in Bot. Jahrb. Syst. 50(4): 370. 1913 |
14' | Petioles usually longer than 10 mm; leaf length/width ratio < 3:1 |
15 | Male inflorescences showing dichasial or monochasial branching with at least the basal internodes > 1 mm long |
15' | Male inflorescences subumbellate, i.e. consisting of strongly compressed cymes with internodes < 1mm long |
16 | Female flowers with 4 subequal tepals Begonia chiasmogyna in Edinburgh J. Bot. 63 (2-3): 193. 2006 |
16' | Female flowers with 5 unequal tepals |
17 | Male flowers with (3-)4 tepals Begonia grandipetala in Bot. Jahrb. Syst. 50(4): 377. 1913 |
17' | Male flower with 2 tepals |
18 | Wings of ovary and fruits < 6 mm at the widest point |
18' | Wings of ovary and fruits > 6 mm at the widest point |
19 | Capsules 13-22 mm long Begonia sphenocarpa in Bot. Jahrb. Syst. 50(4): 369. 1913 |
19' | Capsules < 12 mm long |
20 | Leaves c. 7-11 x 3-6 cm, margin irregularlly dentate to serrate Begonia hispidissima in Meded. Lands Plantentuin 19: 485. 1898 |
20' | Leaves 4.9-6.6 x 1.8-3 cm, margin irregularly incised up to c. halfway to the midrib Begonia masarangensis in Bot. Jahrb. Syst. 50(4): 368. 1913 |
21 | Leaf lamina irregularly incised up to almost halfway to the midrib; tepals of male flowers c. 5 x 5 mm Begonia stevei in Edinburgh J. Bot. 63(2-3): 197. 2006 |
21' | Leaf lamina margin not or only shallowly incised; tepals of male flowers larger than 5 x 5 mm |
22 | Leaves up to 7 cm long; male inflorescences few-flowered (< 6 flowers) Begonia strachwitzii in Bot. Jahrb. Syst. 50(4): 357. 1913 |
22' | Larger leaves > 7 cm long; male inflorescences usu. many-flowered (> 8 flowers) |
23 | Peduncles of female inflorescences > 20 mm |
23' | Peduncles of female inflorescences < 15 mm |
24 | Ovary covered by large bracteoles Begonia bonthainensis in Bull. Misc. Inform. Kew: 37. 1896 |
24' | Ovary not covered by bracteoles Begonia siregarii in Edinburgh J. Bot. 71(2): 263. 2014 |
25 | Tepals of male flowers up to 7 mm long; peduncles of female inflorescences very short (< 2 mm) Begonia insularum in Bot. Jahrb. Syst. 50(4): 353. 1913 |
25' | Tepals of male flowers > 7 mm long; peduncles of female inflorescences > 3 mm long |
26 | Tepals of male flowers ca. 12 x 12 mm, apex slightly pointed; pedicels of female flowers and fruits ca. 12 mm long Begonia macintyreana in Edinburgh J. Bot. 63(2-3): 194. 2006 |
26' | Tepals of male flowers ca. 9-16 x 13-21 mm, apex rounded; pedicels of female flowers and fruits up to 7 mm long Begonia gambutensis in Edinburgh J. Bot. 71(2): 260. 2014 |
27 | Male cymose inflorescences with 2(-3) flowers; leaf laminas < 7 cm long Begonia didyma in Edinburgh J. Bot. 66(2): 230. 2009 |
27' | Male cymose inflorescences with more than 3 flowers; larger leaves > 7 cm long |
28 | Peduncle of compressed, cymose male inflorescences up to 5 mm long |
28' | Peduncles of cymose male inflorescences > 5 mm long |
29 | Plants with macroscopic multicellular hairs on the stems and nerves of the abaxial leaf surfaces Begonia capituliformis in Bot. Jahrb. Syst. 50(4): 354. 1913 |
29' | Plant glabrous except for microscopic glandular hairs |
30 | Petiole 2-5 cm long; leaf lamina 6-14 × 3-7 cm Begonia mekonggensis in Reinwardtia 13(1): 70. 2009 |
30' | Petiole 10-24 cm long; leaf lamina 12–24 × 7–15 cm Begonia hooveriana in Reinwardtia 13(5): 445. 2013 |
31 | Ovaries and fruits with multicellular trichomes each with a conspicuously broad, bulbous base narrowing into a fine extended tip Begonia guttapila in Edinburgh J. Bot. 66(2): 234. 2009 |
31' | Ovaries and fruits glabrous or when with multicellular trichomes, then trichomes without conspicuously broad bulbous base |
32 | Vegetative organs glabrous except for a sparse indumentum of microscopic glandular hairs |
32' | Above-ground vegetative organs with a sparse to dense indumentum of macroscopically visible multicellular simple trichomes |
33 | Number of stamens < 40 Begonia imperfecta in Bot. Jahrb. Syst. 50(4): 367. 1913 |
33' | Number of stamens > 40 |
34 | Small erect herbs < 30 cm in height; tepals of female flowers < 14 mm long Begonia nobmanniae in Edinburgh J. Bot. 68(2): 235. 2011 |
34' | Tall erect herbs or soft-wooded shrubs < 40 cm in height; tepals of female flowers 18-27 mm long |
35 | Compressed subumbellate male partial inflorescences with > 8 flowers, composed of 3-5 compressed monochasia, each with 3-5 flowers; tepals of the female flowers often irregularly serrate at the apex; leaf lamina margin biserrate Begonia torajana in Edinburgh J. Bot. 68(2): 246. 2011 |
35' | Compressed subumbellate male partial inflorescences with < 8 flowers, composed of 2 compressed monochasia, each with 1-3 flowers; tepals of the female flowers with entire margins; leaf lamina margin biserrate to shallowly lobed (up to c.25% to the midrib) Begonia rantemarioensis in Edinburgh J. Bot. 68(2): 240. 2011 |
36 | Peduncles of female inflorescence > 11 mm |
36' | Peduncles of female inflorescences (sometimes reduced to a single flower) < 8 mm |
37 | Margins of the tepals of the female flowers irregularly serrate at apices; pedicels of fruits erect Begonia prionota in Edinburgh J. Bot. 68(2): 237. 2011 |
37' | Margins of the tepals of the female flowers entire; pedicels of fruits apically strongly deflexed Begonia hekensis in Edinburgh J. Bot. 66(1): 110. 2009 |
38 | Tepals of female flowers 15-32 mm long; leaf lamina < 5 cm in width Begonia sanguineopilosa in Edinburgh J. Bot. 68(2): 243. 2011 |
38' | Tepals of female flowers < 15 mm long, or when slightly longer (B. sphenocarpa) then larger leaves > 5 cm in width |
39 | Petioles glabrous or very sparsely hairy with macroscopically visible multicellular hairs; teeth of the leaf lamina not extended into fine bristles Begonia nobmanniae in Edinburgh J. Bot. 68(2): 235. 2011 |
39' | Petioles densely hairy with macroscopically visible multicellular hairs; teeth of the leaf lamina extended into fine bristles |
40 | Ovary wings not hairy at the margins; leaves 5-8 × 3-4.5 cm Begonia celebica in Bot. Jahrb. Syst. 50(4): 343. 1913 |
40' | Ovary wings hairy at the margins; leaves 7-21.5 × 5-12.5 cm |
41 | Leaf margin serrate; fruits < 15 mm long; tepals of female flowers 10-12 mm long Begonia lasioura in Edinburgh J. Bot. 68(2): 233. 2011 |
41' | Leaf margin biserrate; fruits > 18 mm long; tepals of female flowers 12-17 mm long Begonia sphenocarpa in Bot. Jahrb. Syst. 50(4): 369. 1913 |
42 | Fruits dehiscent, three wings well developed along the whole length of the fruit Begonia watuwilensis in Reinwardtia 13(1): 70. 2009 |
42' | Fruits fleshy and indehiscent, wings strongy reduced and not all three wings fully developed along the whole length of the fuits |
43 | Leaves oblong-lanceolate Begonia aptera, Enum. Pl. Javae 1: 97. 1827 |
43' | Leaves broadly ovate |
44 | Plant glabrous Begonia rieckei in Bot. Jahrb. Syst. 13(3-4): 387. 1891 |
44' | Plant hairy |