Begonia cucullata Willd.

Moonlight, Peter & Fuentes, Alfredo F., 2022, AN UPDATED CHECKLIST AND KEY TO THE SPECIES OF BOLIVIAN BEGONIA, INCLUDING ONE NEW SPECIES, Edinburgh Journal of Botany 79 (407), pp. 1-66 : 24-25

3.17. Begonia cucullata Willd. , 4(1): 414 (1805). – Type: Unknown.

A.P. de Candolle, Fl. Bras. 4: 341 (1861); A. Grisebach, Symb. Fl. Argent. 24: 136 (1879); M.C. Tebbitt, Begonian 79: 99 (2012); D.C. Wasshausen et al. in P.M. JØrgensen et al. (eds), Cat. Bolivia, Monogr. Syst. Bot. Missouri Bot. Gard. 129: 384 (2013); Delfini, C. in Zuloaga, F.O. & Belgrano, M.J. (eds), Fl. Argentina 17: 5 (2017).

Begonia obovatistipula C.DC. , Bulletin de la Societe Botanique de Geneve, Ser. 2, 6: 124, fig. VI (1914). – Type: Paraguay, [Concepción Department], Zweischen río Apa und río Aquidaban , Villareal , Rieden Camp , [22°39′S, 57°45′W], 1908–1909, K. Fiebrig 4514 (lectotype G [ G00077061 (2 sheets)] designated here; isolectotypes B [ B100247915 ], G [2: G00077057 (2 sheets)]), syn. nov .

Distribution. Known from Brazil, Paraguay, Argentina and Bolivia, and widely introduced elsewhere.

Nomenclatural notes. The protologue of Begonia cucullata cites material collected in Brazil ( Willdenow, 1805). It is unclear whether this refers to a herbarium collection, and if so, where it is deposited. We refrain from designating a neotype while it remains unclear whether any material suitable for lectotypification exists. The protologue of Begonia obovatistipula cites material of the collection K. Fiebrig 4515, for which we know of duplicates in Berlin and the general herbarium in Geneva ( de Candolle, 1914). Anne Casimir Pyramus de Candolle was based in Geneva, so it is appropriate to designate a type from the material in Geneva. We select the duplicate G00077061 as the lectotype, which has two sheets and a greater quantity of fertile material than the alternatives.

Synonymy notes. Begonia cucullata is a widespread species native to Brazil, Paraguay, Bolivia and Argentina, with scattered naturalised records throughout northwest South America and Central America ( Hughes et al., 2015 –). Previous classifications recognised three varieties within this species ( Smith & Schubert, 1941b), but Jaramillo (2017) recognised Begonia cucullata as a single, variable species with no varieties. The type specimens, description, and all Bolivian specimens of Begonia obovatistipula fall within the range of variation recognised by Jaramillo, so we transfer B. obovatistipula into synonymy with B. cucullata herein.

Identification notes. Begonia cucullata is a variable species but is easily recognised in Bolivia because it is a small (usually <50 cm tall, always <1 m tall), completely glabrous herb with cucullate leaf bases. All similar species are easily distinguished by their sparse to dense indumentums.