Rubus borbonicus Persoon (1806: 51)

Beek, Abraham Van De, 2021, Rubi Capenses: a further contribution to the knowledge of the genus Rubus (Rosaceae) in South Africa, Phytotaxa 515 (1), pp. 1-71 : 22

b. Rubus borbonicus Persoon (1806: 51)

Homotypic synonym:— Rubus tomentosus Bory de Saint-Vincent (1804: 375) , non Borkhausen (1794: 2), nom. illegit.

Lectotype (designated here):— RÉUNION. ‘ Rubus borbonicus Pers. Bourbon. Legit Bory’ ( P02579816 [https://science.mnhn.fr/institution/ mnhn/collection/p/item/p02579816]) .

Notes: — Persoon (1806), in the protologue of R. borbonicus , explicitly refers to R. tomentosus Bory as identical and the details of the description are borrowed from Bory’s publication. So R. borbonicus is a homotypic synonym of the illegitimate R. tomentosus Bory.

There are two specimens collected by Bory in P. On the label of the first one is written: ‘ Rubus tomentosus / nob. var./ en arivant a la/ plaine des cafres/ a Bourbon’ (P02520892). It could not be selected as type because of the addition ‘var.’; the combination ‘nob.’ and ‘var.’ suggests that Bory already acknowledged a species R. tomentosus and considered this plant as a variety. It has stronger curved prickles, narrow leaves, an open inflorescence, shorter ovate sepals, but on the other hand very clearly the conspicuous serrature of R. borbonicus . It may be a form from a sunny place.

The other sample collected by Bory consists of some broken off leaflets and a piece of an inflorescence stem (P02579816). Richard wrote on the label ‘ Rubus borbonicus Pers. Bourbon. Legit Bory’. Though it is not written by Bory, it is clear that the specimen was collected by him, and because no other specimen is available it was selected as the lectotype.

The non-flowering branch (either a very young primocane or a secondary shoot) of the type of R. apetalus is not very characteristic. The inflorescence of the type is more characteristic and there is no reason to not identify R. borbonicus with it. Earlier authors (except Gustafsson 1934) drew the same conclusion. Consequently R. borbonicus is a later synonym of R. apetalus .