Steningebjörnbär, ett nygammalt krypbjörnbär från Halland

Rubus sordirosanthus (sect. Corylifolii Lindl.) was published, although invalidly, by Hylander 1958 from the province of Halland, south-western Sweden. A holotype is here provided to make the name validly published. Recent field studies have shown that it occurs at almost 100 localities in a restricted area of c. 6 km around Steninge in central Halland. In addition, it is found on a former refuse tip in the city of Halmstad, 23 km to the south. A morphologically similar form has been found in three places at roadsides around the city of Varberg, 33 km to the north. We have used genetic methods to investigate the relation between these forms and the related species R. wahlbergii Arrh. The chromosome number of R. sordirosanthus from Steninge and Halmstad, as well as the Varberg form is 2n=28, in contrast to 2n=35 for R. wahlbergii. Moreover, RAPD DNA analysis shows that the two species are genetically separated. Rubus sordirosanthus from Steninge and Halmstad is homogeneous, whereas the Varberg form differs, although not in the direction towards R. wahlbergii. The latter species is genetically quite diverse. Thus, R. sordirosanthus is a well-defined and locally abundant species in Halland. On the other hand, the Varberg form gives the impression of being introduced in Varberg and therefore probably occurs also in other areas.