Begonia diversifolia var. nana Walp.

Moonlight, Peter. W., Jara-Muñoz, Orlando A., Purvis, David A., Delves, Jay, Allen, Josh P. & Reynel, Carlos, 2023, The genus Begonia (Begoniaceae) in Peru, European Journal of Taxonomy 881, pp. 1-334 : 304

Begonia diversifolia var. nana Walp.

Novorum Actorum Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum 19 (suppl. 1): 408 ( Walpers 1843b). – Begonia hirtella var. nana (Walp.) A.DC. , Flora Brasiliensis 4 (1): 345 ( de Candolle 1861).

– Type: PERU • ad Altos de Toledo , F.J.F. Meyen [n.v., herbarium unknown].

de Candolle (1864: 299).

Notes

Walpers described B. diversifolia var. nana Walp. based upon a collection made by F.J.F. Meyen ( Walpers 1843b: 409). Meyen’s collection was made in Altos de Toledo, a pass between the cities of Puno and Arequipa ( Weberbauer 1936). Almost without exception, the full length of all passes between these cities are above 4000 m in elevation and are dry, high elevation grasslands unsuitable for Begonia species. This is a variety of B. diversifolia Graham , which is a member of B. sect. Quadriperigonia Ziesenh. and only distantly related to any Peruvian Begonia species ( Moonlight et al. 2018). The description provided by Walpers is insufficient to identify this specimen to any known Peruvian species. Alphonse Pyramus de Candolle moved this taxon to a variety of B. hirtella in his Flora of Brazil account and cited several Brazilian specimens of B. hirtella as the same variety ( de Candolle 1861) and later repeated this citation ( de Candolle 1864). It is unclear whether de Candolle saw the type of B. diversifolia var. nana . He also cited a specimen collected by Meyen in Rio de Janeiro, which is a syntype of Walper’s B. meyeniana Walp. (a taxon of uncertain application; Jacques & Mamede 2005). It is possible de Candolle confused these specimens or also that Walpers confused the type locality of the two specimens. Walper’s herbarium was sold upon his death and the location of his specimens are unknown. We have been unable to locate any specimens matching his description. Given the considerable uncertainty surrounding the type locality, protologue description, and classification of this species, we suggest that if the type specimen cannot be located that this name should be rejected.