Rubus opacus Focke ex Bertram

Focke published the name Rubus opacus in Alpers' Flora of Stade (1875) without a description. His remark that the plant is intermediate between R. plicatus and R. affinis cannot be considered as a description because he does not even mention in which characteristics it differs from these species (cf. ICN art. 38.2, ex. 4). The name was validly published by Bertram (1876) who collected plants that he considered to be the same species. Braun found out that this was not the case and gave Bertram's plants the name Rubus bertramii (Braun 1876). At first sight this seems a superfluous name because R. opacus Focke ex Bertram seems to be included. This is however not necessary. It depends on the type of R. opacus Focke ex Bertram. Becaus Bertram does not only refer to his own plants but also to those of Focke and explicitly mentions their localitities one can also select a lectotype from these. Therefore I chose as lectotype of R. opacus Focke ex Bertram the same specimen as has been selected previously for R. opacus Focke (BREM, Focke, Lesum bei Bremen, 6.8.1869, the leaf only). So the name can be saved and only an addition to the authors indication 'ex Bertram' is needed. R. bertramii Braun is then R. opacus Bertram typo excluso and also a legitimate name. It is the correct name for the plants that Bertram collected himself. 

Literature:

Alpers, F. 1875. Verzeichniss der Gefässpflanzen der Landdrostei Stade. Fr. Schaumburg, Stade.

Bertram, F.W.W.  1876. Flora von Braunschweig. Vieweg, Braunschweig.

Braun, G. 1877-1881. Herbarium Ruborum Germaniae.