Phylogenetic relationships within <i>Silene</i> (Caryophyllaceae) section <i>Physolychnis</i>

Abstract

Abstract Phylogenetic relationships within Silene sect. Physolychnis are investigated using DNA sequences from two low‐copy nuclear regions and three plastid regions. We expand the circumscription of Physolychnis to include also Siberian and Eurasian taxa, with S . zawadzkii and S . uralensis as delimiters of the section. Two main clades are identified within Physolychnis , the Siberian S . ajanensis group and an Asian/American clade. Several taxa, previously classified to sect. Odontopetalae , sect. Occidentales , and sect. Morrisonmontanae , are shown to belong to the Asian/American clade, which otherwise corresponds to Bocquet's (1969) circumscription of sect. Physolychnis . Silene sect. Physolychnis also includes several additional, mainly Asian taxa (e.g., S . davidii , S . seoulensis , S . keiskei , S . viscosa , S . quadriloba , and homoeologues from S . songarica , S . firma , and S . tolmatchevii ). Several putative allopolyploids are identified, in several cases stemming from crosses between the two main clades. The two allotetraploids S . involucrata and S . sachalinensis , although morphologically and geographically distinct, have indistinguishable ancestries.