Taxonomy and phylogeography of Cardamine impatiens and C. pectinata (Brassicaceae).

The taxonomic position of Cardamine pectinata, a controversial taxon treated either as infraspecific to C. impatiens or as a separate species, was studied. Forty-nine populations were sampled and used in multivariate morphometric and molecular (amplified fragment length polymorphism) analyses. Our results showed that C. impatiens and C. pectinata represent two well-differentiated taxa in terms of both molecular and morphological data, and should be treated as two separate species. We present the taxonomic conspectus for both species, including the list of synonyms, information on type specimens, morphological descriptions, ecological characteristics, and distribution area. Type specimens for several names are designated here. The detailed geographical distribution of C. pectinata is presented based on the survey and revision of herbarium material. It covers the area from the Balkans through Turkey and the Caucasus to Iran. As an introduction to the phylogeography of both species, the distribution of genetic diversity within and between the studied populations and geographical regions was assessed. In C. pectinata, the highest genetic diversity was observed in northern Turkey, suggesting the location of glacial refugia along the Black Sea coast. Populations in Bulgaria were less diverse, and this area has most probably been colonized postglacially. C. impatiens, on the other hand, did not display clear phylogeographical structure, most probably as a result of the efficient spread and mixing between different colonization routes. [ABSTRACT FROM AUTHOR]