Begonia (sect. Ruizopavonia) De Candolle 1859 Author Moonlight, P. W. Royal Botanic Garden Edinburgh, 20 A Inverleith Row, Edinburgh EH 3 5 LR, Scotland, UK. E-mail: pmoonlight @ rbge. ac. uk. pmoonlight@rbge.ac.uk. Author Pérez, Á. J. Herbario QCA, Department of Biological Sciences, Pontificia Universidad Católica del Ecuador, Apartado Postal 17 - 01 - 2184, Quito, Ecuador. text Edinburgh Journal of Botany 2022 2022-08-18 79 401 1 9 http://dx.doi.org/10.5281/zenodo.8389628 journal article 10.24823/EJB.2022.401 1747-0036 Key to the Colombian and Ecuadorian species of Begonia sect. Ruizopavonia 1a. Stipules persistent, remaining on the stem long after the leaves Begonia tonduzii C.DC. 1b. Stipules early deciduous, lost before the leaves are fully grown _____________________ 2 2a. Inflorescence internodes elongated,> 5 mm long; pistillate flowers with 3 of 5 tepals see key in Tebbitt et al. (2017) 2b. Inflorescence internodes short, < 2 mm long; pistillate flowers with 2 or 3 tepals ____ 3 3a. Staminate flowers with 2 tepals ______________________________ Begonia alnifolia A.DC. 3b. Staminate flowers with 4 tepals ___________________________________________________ 4 4a. Tepals on the staminate and pistillate flowers> 10 mm long, orange, apices long-acuminate ______________________ Begonia cuatrecasasiana L.B.Sm. & B.G.Schub. 4b. Tepals on the staminate and pistillate flowers < 10 mm long, white to pink, apices rounded, glabrous on both surfaces ________________________________________________ 5 5a. Terrestrial herb to> 5 m tall; bracteoles lacking; 2 tepals on the pistillate flowers Begonia pseudodendron 5b. Terrestrial herb to < 2 m tall; 2 or 3 bracteoles present directly beneath the ovary, persistent; 3 tepals on the pistillate flower (unknown in Begonia dugandiana ) ________ 6 6a. Stamens c.20; leaf laminae with 6–8 secondary veins on the broadest side; styles unknown but presumed bifid _______________ Begonia dugandiana L.B.Sm. & B.G.Schub. 6b. Stamens> 25; leaf laminae with 8–12 secondary veins on the broadest side; styles multifid ___________________________________________________________________________ 7 7a. Leaf laminae straight, ovate; inner tepals on the staminate flower c.5 × 2 mm Begonia cymbalifera L.B.Sm. & B.G.Schub. 7b. Leaf laminae transversely ovate; inner tepals on the staminate flower c.3 × 1 mm Begonia consobrina Irmsch.