A phylogeographic analysis ofViola rupestris: three post-glacial immigration routes into the Nordic area?

Morphology and isoenzyme patterns support the taxonomic delimitation of two subspecies ofViola rupestrisF. W. Schmidt in the Nordic area, i.e. ssp.rupestrisand ssp.relictaJalas. Three different, geographically distinctly defined genotypes, are revealed (based on seven enzyme systems): one in north Scandinavia (= ssp.relicta, distinct in AAT-1, AMP-1 and PGM-3), one in north Finland (distinct in AMP-2), and one widespread in the southern and central parts of Norden. Two of the three unique bands in ssp.relictaare also detected in British material. The data are consistent with the scenario of three post-glacial immigration routes into the Nordic area: one from the south-west, today represented by the north Scandinavian populations, one from the east, today represented by the populations in the Kuusamo area of north Finland, and one from the south-east, today represented by widespread populations south of the mentioned areas.