A phylogenetic study of Dipsacaceae, a Mediterranean­centered clade in the Dipsacales, was conducted using nuclear ITS and three chloroplast markers (atpB ­ rbcL, trnL­ trnF, trnSUGA­ trnGGCC). This is the first molecular study to assess Dipsacaceae phylogeny in detail, and includes representatives from all major subclades. Maximum parsimony, maximum likelihood, and Bayesian analyses were carried out on the ITS and plastid datasets separately and in combination. For the most part, the ITS and plastid datasets resulted in similar topologies, and the combined data yielded a well­resolved estimate of Dipsacaceae phylogeny. A small Asian clade composed of Bassecoia and Pterocephalodes hookeri is resolved as sister to the rest of Dipsacaceae. Scabioseae s. str. (Scabiosa, Sixalix, Pterocephalus s. str., Lomelosia , Pycnocomon) and a "Dipknautid" clade (Dipsacus, Cephalaria, Knautia, Pterocephalidum, Succisa, Succisella, Pseudoscabiosa) form the two major lineages within Dipsacaceae. Most of the previously recognized genera are recovered as monophyletic, with the exception of Pycnocomon, which is nested within Lomelosia. We discuss the taxonomic implications of these results and their significance for understanding character evolution, particularly of the epicalyx in relation to seed dispersal.

BackgroundCYCLOIDEA (CYC)-like genes have been implicated in the development of capitulum inflorescences (i.e. flowering heads) in Asteraceae, where many small flowers (florets) are packed tightly into an inflorescence that resembles a single flower. Several rounds of duplication of CYC-like genes have occurred in Asteraceae, and this is hypothesized to be correlated with the evolution of the capitulum, which in turn has been implicated in the evolutionary success of the group. We investigated the evolution of CYC-like genes in Dipsacaceae (Dipsacales), a plant clade in which capitulum inflorescences originated independently of Asteraceae. Two main inflorescence types are present in Dipsacaceae: (1) radiate species contain two kinds of floret within the flowering head (disk and ray), and (2) discoid species contain only disk florets. To test whether a dynamic pattern of gene duplication, similar to that documented in Asteraceae, is present in Dipsacaceae, and whether these patterns are correlated with different inflorescence types, we inferred a CYC-like gene phylogeny for Dipsacaceae based on representative species from the major lineages.ResultsWe recovered within Dipsacaceae the three major forms of CYC-like genes that have been found in most core eudicots, and identified several additional duplications within each of these clades. We found that the number of CYC-like genes in Dipsacaceae is similar to that reported for members of Asteraceae and that the same gene lineages (CYC1-like and CYC2B-like genes) have duplicated in a similar fashion independently in both groups. The number of CYC-like genes recovered for radiate versus discoid species differed, with discoid species having fewer copies of CYC1-like and CYC2B-like genes.ConclusionsCYC-like genes have undergone extensive duplication in Dipsacaceae, with radiate species having more copies than discoid species, suggesting a potential role for these genes in the evolution of disk and ray florets. The similarity in CYC-like gene diversification seen in Dipsacaceae and some members of the Asteraceae sets the stage to investigate whether the convergent evolution of capitulum inflorescences in both groups may have been underlain by convergent evolution in the same gene family.

Aim  To reconstruct the temporal and biogeographical history of Old World disjunctions in Scabiosa (Dipsacaceae) and the timing of diversification in the Mediterranean Basin, in order to evaluate the importance of biogeographical and climatological history (particularly the onset of a mediterranean climate) in shaping Scabiosa distributions. Location  Europe and the Mediterranean Basin, southern Africa and eastern Asia. Methods  This study uses maximum‐likelihood and Bayesian phylogenetic analyses of chloroplast DNA (atpB–rbcL, trnL–trnF, trnS–trnG, psbA–trnH) and nuclear ribosomal DNA [internal transcribed spacer (ITS) and external transcribed spacer (ETS)] from 24 out of c. 37 ingroup taxa, beast molecular dating, and the dispersal–extinction–cladogenesis method (Lagrange) to reconstruct ancestral geographical ranges and the timing of diversification of the major clades of Scabiosa. Results  Biogeographical and divergence time reconstructions showed that Scabiosa originated during the Miocene and diversified in Europe, followed by independent movements into Asia and Africa. Several of the major clades were inferred to have radiated sometime between the late Miocene and early Pleistocene, a timeframe that encompasses the onset of the mediterranean climate in Europe. More recent middle–late Pleistocene radiations in the Mediterranean Basin and southern Africa have played a large role in Scabiosa diversification. Main conclusions  Members of Scabiosa appear to have capitalized on adaptations to montane and/or dry conditions in order to colonize similar habitats in different biogeographical regions. The formation of the East African Rift mountains is potentially of great importance in explaining the southward migration of Scabiosa. The initial diversification of Scabiosa in Europe during the Miocene is not consistent with the initiation of the mediterranean climate, but may instead be associated with increased aridity and the retreat of subtropical lineages during this time. However, the radiation of some of the major subclades within Scabiosa may have been associated with an emerging mediterranean climate. More recent and rapid radiations in both the Mediterranean Basin and southern Africa highlight the probable importance of Pleistocene climate fluctuations in Scabiosa diversification.