Phylogeny of the Inula group (Asteraceae: Inuleae): Evidence from nuclear and plastid genomes and a recircumscription of Pentanema

Abstract The Inula complex (Asteraceae: Inulinae) is a monophyletic group which comprises eight genera distributed in Eurasia and Africa: Amblyocarpum, Carpesium, Chrysophthalmum, Inula, Pentanema, Rhanteriopsis, Telekia , and Varthemia. With the aim to shed light on the circumscription of these genera, phylogenetic analyses were performed with 293 new DNA sequences (ITS region from nrDNA and three plastid spacers from cpDNA: rps16–trnQ, rpl32–trnL, ndhF–rpl32). It is concluded that both Inula and Pentanema are paraphyletic and that generic delimitations within the Inula complex need to be revised. Based on the results of the analyses, together with morphological and karyological data, we argue that the best solution is a new circumscription of the genus Pentanema including an amended description and 24 new combinations of former Inula species. Resurrection of the names Codonocephalum, Monactinocephalus and Vicoa is proposed to preserve the monophyly of the genera included in the Inula complex. Incongruences between nrDNA and cpDNA are documented and discussed.