Cirsium ×sudae

Abstract

In this study we describe a new nothospecies, Cirsium ×sudae Michálková et Bureš, a homoploid hybrid between two rare Alpine species, C. carniolicum and C. greimleri. Hybrid status was confirmed for four morphologically intermediate individuals, found in the Ennstal Alps, Austria (three of them were F1 hybrids and one a backcross with C. carniolicum). We used amplified fragment length polymorphism (AFLP) to confirm affiliation to the parental species and exclude the potential contribution of other sympatric species. In addition, we used flow cytometry to confirm the diploid status of this hybrid. The newly assessed genome size of this hybrid is 2C = 1.99±0.03 pg, and for C. carniolicum 2C = 2.03±0.04 pg.