Homoploid hybrid speciation in Doronicum L. (Asteraceae)? Morphological, karyological and molecular evidences

The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae - Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum x minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) x D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation.