Genetic Variation versus Morphological Variability in European Peatland Violets (- Group).

In Europe, the - group comprises Ledeb., L., (Kuta) G. H. Loos (= subsp. Kuta), interspecific hybrids, and putative introgressants. The genetic affinity of to , and their shared origin via hybridization followed by polyploidization, were confirmed using inter simple sequence repeat (ISSR) markers, restriction site-associated DNA sequencing (RAD-Seq), and a low-copy nuclear gene, , which encodes glucose-6-phosphate isomerase. The other taxa of subsect. were not identified as putative parents of by . Our analyses indicated that can be included in the morphological and genetic variation of . The ISSR, RAD-Seq, and genome size value separated well from and hybrids. The results also reopen the discussion on intraspecific variation in the context of taxa ranks and species concepts. The reduced tolerance of in Europe to changing environmental conditions might result from low genetic differentiation and heterozygosity, as well as the increased number of interspecific hybrids ( × ), and eventually can possibly lead to its extinction. The disappearance of populations/individuals of this species may indicate anthropogenic changes occurring in peatlands.