Begonia sect. Ruizopavonia, De Candolle, 1859

Jara-Muñoz, O. A., Moonlight, P. W. & Zabala-Rivera, J. C., 2023, A New Species of Begonia (Begoniaceae) from the Eastern Cordillera of Colombia, Phytotaxa 616 (2), pp. 169-175 : 173-174

Key to the Colombian species of Begonia sect. Ruizopavonia [based on Tebbitt et al. (2017) and Moonlight & Pérez (2022)]

1. Stipules persistent, remaining on the stem long after the leaves........................................................................................................2

- Stipules early deciduous, lost before the leaves are fully grown .......................................................................................................3

2. Inflorescence branched; staminate flowers with 2 tepals and pistillate flowers with 4 tepals; wings of the fruit lunulate ................. ................................................................................................................................................................................. B. tonduzii C.DC.

- Inflorescence unbranched; staminate flowers with 4 tepals and pistillate flowers with 5 tepals; wings of the fruit deltate triangular................................................................................................................................................... B. embera Jara & D.Franco

3. Inflorescence internodes short, <2 mm long; pistillate flowers with 3 or 5 tepals............................................................................4

- Inflorescence internodes elongated,> 5 mm long; pistillate flowers with 2, 3 or 4 tepals ................................................................5

4. Stem and petioles glabrous; stamens ca. 20; pistillate tepals 3; ovary wing rounded.................. B. botryoides Moonlight & Tebbitt

- Stem and petioles villous; stamens ca. 8–12; pistillate tepals 5; ovary wing triangular ........................................ B. tiliifolia C. DC.

5. Staminate flowers with 2 tepals..........................................................................................................................................................6

- Staminate flowers with 4 tepals..........................................................................................................................................................8

6. Pistillate flowers with 4 tepals; filaments exceeding the anthers in length..................... Begonia xylopoda L.B. Sm. & B.G. Schub.

- Pistillate flowers with 2 or 3 tepals; anthers exceeding the filaments in length.................................................................................7

7. Staminate tepals 4–5 mm long; connective shorter than the theca; pistillate flowers with 2 tepals ............. Begonia alnifolia A.DC.

- Staminate outer tepals ca. 16 mm long; connective as long as or exceeding the length of the theca; pistillate flowers with 3 tepals Begonia extensa L.B. Sm. & B.G. Schub.

8. Outer tepals on the staminate and pistillate flowers> 10 mm long ...................................................................................................9

- Outer tepals on the staminate and pistillate flowers <10 mm long .................................................................................................10

9. Leaves straight; bracts persistent; tepals orange or red with long-acuminate apex ............................................................................. ............................................................................................................................... Begonia cuatrecasasiana L.B.Sm. & B.G.Schub.

- Leaves transverse; bracts deciduous; tepals white or pink with rounded apex ...... Begonia betancurii Jara & Moonlight sp. nov.

10. Terrestrial herb to> 5 m tall; bracteoles lacking; pistillate flowers with 2 tepals... Begonia pseudodendron Moonlight & A.J.Pérez

- Terrestrial herb to <2 m tall; 2 or 3 bracteoles present directly beneath the ovary, persistent; pistillate flower with 3 tepals .......11

11. Peduncle hirsute; leaf laminae with 6–8 secondary veins on the broadest side; stamens c.20 ............................................................ ...................................................................................................................................... Begonia dugandiana L.B.Sm. & B.G.Schub.

- Peduncle glabrous; leaf laminae with 8–12 secondary veins on the broadest side; stamens> 25 ....................................................... ...................................................................................................................................... Begonia cymbalifera L.B.Sm. & B.G.Schub.