Taxonomy of the Rubus gothicus group in south-eastern central Europe

Rubus ser. Subthyrsoidei is a particularly intricate group within the sect. Corylifolii due to its phenologically and ecologically driven plasticity and variability. In the recent study we investigated the narrower-leaved biotypes of the series in south-eastern central Europe that represent a distinct entity often called "Rubus gothicus group". We recognized four stable biotypes (apomictic species) occurring in the area: (1) the north-central European R. gothicus s. str., which was rarely found in northern Bohemia; (2) a biotype from south-eastern Silesia that was shown to be conspecific with R. subgothicus, a here lectotypified, formerly overlooked species; (3) a new species from the southern part of the Czech Republic and northern Austria, R. lobifolius, which was included by earlier authors in R. gothicus s. str.; and (4) another new species, R. scarbantinus, which is common in the eastern foothills of the Alps. Flow cytometric measurements confirmed that all the here circumscribed species of the R. gothicus group are tetraploid. We provided a taxonomic and nomenclatural discussion, revised morphological description, ecological characteristics and distribution maps for the species studied.