Dianthus broteri shows the highest diversity of cytotypes known to date in the genus Dianthus. Moreover, some cytotypes present remarkable internal genome size variation. The evolution of the complex is discussed in terms of autopolyploidy, with primary and secondary contact zones.

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Mutualistic services by ant are essential for the pollination of Cytinus hypocistis. Although this parasite does not exhibit typical features of the 'ant-pollination syndrome', many other characteristics indicate that it is evolving to a more specialized ant-pollination system. The striking interspecific differences in the pollination systems of Mediterranean Cytinus (ant-pollinated) and some South African Cytinus (mammal-pollinated) make this genus an excellent model to investigate the divergent evolution of pollination systems in broadly disjunct areas.

Summary• Chromosomal duplications and increases in DNA amount have the potential to alter quantitative plant traits like flower number, plant stature or stomata size. This has been documented often across species, but information on whether such effects also occur within species (i.e. at the microevolutionary or population scale) is scarce.• We studied trait covariation associated with polyploidy and genome size (both monoploid and total) in 22 populations of Dianthus broteri s.l., a perennial herb with several cytotypes (2x, 4x, 6x and 12x) that do not coexist spatially. Principal component scores of organ size ⁄ number variations were assessed as correlates of polyploidy, and phylogenetic relatedness among populations was controlled using phylogenetic generalized least squares.• Polyploidy covaried with organ dimensions, causing multivariate characters to increase, remain unchanged, or decrease with DNA amount. Variations in monoploid DNA amount had detectable consequences on some phenotypic traits. According to the analyses, some traits would experience phenotypic selection, while others would not.• We show that polyploidy contributes to decouple variation among traits in D. broteri, and hypothesize that polyploids may experience an evolutionary advantage in this plant lineage, for example, if it helps to overcome the constraints imposed by trait integration.