Western Ukrainian Cochlearia (Brassicaceae)—the identity of an isolated edge population

A strongly isolated population of Cochlearia in North‐Western Ukraine was analysed using highly discriminating AFLP markers, to clarify the confusing taxonomy of the genus at the eastern edge of its distribution in Europe. The analysis revealed a high level of similarity between the Ukrainian population and C. pyrenaica , supporting its inclusion within this species and not within C. polonica . Cochlearia polonica remains a narrowly distributed endemic of the Polish lowlands. Most genetic variability of the Central European populations of the diploid C. pyrenaica (Ukraine, Carpathians, Alps) was found among populations. In addition, the populations significantly differentiated into two distinct groups (Alps versus Carpathians and Ukraine). The strong genetic divergence of the Ukrainian population together with its low within population variability (similarity indices between individuals exceeding 0.9) highlights the need for conservation efforts to prevent the irreversible loss of this distinct gene pool of C. pyrenaica .