Morphological and environmental variability ofDianthus sylvestris(Caryophyllaceae) in the Balkan Peninsula

AbstractSpecies with wide ranges often exhibit morphological variability that is mostly shaped by ecological and evolutionary processes, and the resulting diversity is frequently reflected in intraspecific taxonomy. Dianthus sylvestris in the Balkan Peninsula encompasses six subspecies (D. sylvestris subspp. alboroseus, bertisceus, kozjakensis, nodosus, sylvestris and tergestinus), the identification of which is problematic due to a great morphological variability and complex patterns of environmental variation. To explore morphological variation of described subspecies and to investigate how their morphology varies in relation to environmental variations across their geographical distribution, we evaluated 97 populations of D. sylvestris for variability in 25 morphological characters and 20 environmental variables. Number and shape of epicalyx scales, calyx length and petal denticulation captured the greatest extent of morphological variability between populations. Morphometric analyses revealed a continuous variability in quantitative morphological characters and an absence of clear morphological differentiation between the investigated subspecies. However, two main morphologically distinct entities, the north-western Balkan populations and the south-eastern Balkan populations, were identified and they were split approximately along the Neretva River valley. In addition, our results indicate that environment, rather than geography, plays a potentially more important role in shaping the morphological variability of this taxon. Overall, our results do not support the recognition of the described subspecies or the currently accepted taxonomic concept, instead pointing to a continuous morphological variability of D. sylvestris in the Balkan Peninsula.