1.3. Begonia cinnabarina Hook., Bot. Mag. 75: t. 4483 (1849).

– Type: t. 4883 in W.J. Hooker, Bot. Mag. 75: t. 4483, designated in: Edinburgh J. Bot. 75(2): 252 (2018) by Tebbitt, M.C., Andrada, A.R., Bulacio, E., Parada, G.A. & Ayharde, H.

L.B. Smith & B.G. Schubert, Revista Univ. (Cuzco) 33(87): 77 (1944); R.C. Foster, Contr. Gray Herb. 184: 137 (1958); D.C. Wasshausen et al. in P.M. JØrgensen et al. (eds), Cat. Bolivia, Monogr. Syst. Bot. Missouri Bot. Gard. 129: 384 (2013); M.C. Tebbitt et al., Edinburgh J. Bot. 75(2): 153 (2020); M.C. Tebbitt, Tuberous Begonias, a Monograph of Begonia sect. Australes 78 (2020).

Begonia aurantiaca hort. ex Planch. nom. rej., Fl. Serres Jard. Eur. 8: 530 (1853).

Begonia micranthera var. fimbriata L.B.Sm. & B.G.Schub., Darwiniana 4: 98 (1941b). – Type: Argentina, Prov. Salta, Hills back of Tartagal, [22°30′S, 63°49′W], 500 m, 23 ii 1937, J. West 8413 (holotype GH [GH00068253], isotype MO [2: MO-313008, MO-1643427], NA [NA0026189], UC [UC565008]) .

R.C. Foster, Contr. Gray Herb. 184: 137 (1958); M.C. Tebbitt et al., Edinburgh J. Bot. 75(2): 153 (2020).

Distribution. Bolivia and Argentina.

Identification notes. Begonia cinnabarina is best recognised by its flowers with spreading, broadly ovate and bright cinnabar-red tepals with rounded apices. Two other tuberous Bolivian species have bright red tepals: Begonia veitchii Hook.f. and B. boliviensis . The former is best distinguished by its leaf blades, which have no distinct apex, whereas the tepals of Begonia boliviensis are lanceolate with acuminate apices and are held projecting.