Begonia sect. Hydristyles A.DC. Annales des Sciences Naturelles Botanique, Série 4 11: 132 (de Candolle 1859). – Type: lectotype: Begonia bridgesii A.DC., designated by Barkley & Baranov (1972: 4). Synonymy notes For a full list of sectional synonyms, see Moonlight et al. (2018). Notes This section was erected to include species with multifid styles, five tepals on the pistillate flowers, and two tepals on the staminate flowers (de Candolle 1859: 132). Since the description of several species considered members of B. sect. Ruizopavonia or B. sect. Cyathocnemis with multifid styles (see Doorenbos et al. 1998; Moonlight & Reynel 2018), the delimitation of this section has become less clear. This lack of clarity is only exacerbated by the fact that almost half of species now included in B. sect. Cyathocnemis have five tepals on the pistillate flower. Few members of B. sect. Hydristyles have been included in molecular phylogenies and we suspect its current circumscription will not survive contact with rigorous phylogenetic analysis. The centre of diversity of B. sect. Hydristyles is Bolivia and only two species reach Peru. Both are newly recorded for Peru herein, but we also newly synonymise Peruvian endemic B. peltigera Irmsch. with B. unilateralis.

Published as part of Moonlight, Peter. W., Jara-Muñoz, Orlando A., Purvis, David A., Delves, Jay, Allen, Josh P. & Reynel, Carlos, 2023, The genus Begonia (Begoniaceae) in Peru, pp. 1-334 in European Journal of Taxonomy 881 on page 186, DOI: 10.5852/ejt.2023.881.2175, http://zenodo.org/record/8178280