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Floristic relationships between the Irano-Turanian and Mediterranean regions have been known from old. However, only a few biogeographical analyses based on molecular data have evaluated the history of steppe plants within the Mediterranean basin. Our study aims to contribute to a better understanding of the migratory and diversification processes by reconstructing the biogeography of Rhaponticoides (Cardueae), distributed in the Mediterranean and Irano-Turanian regions. We generated nuclear and plastid sequences that were analyzed by Bayesian inference. We used the resulting phylogeny for dating the diversification of the genus and examining the dispersal pathways. Two clades were recovered, an Irano-Turanian clade and a Mediterranean clade. The origin of the genus was placed in the Anatolian plateau in the Middle Miocene. The genus experienced several diversifications and expansions correlated to the Messinian salinity crisis and the environmental changes in the Pliocene and the Quaternary. Rhaponticoides migrated following two routes reflecting the two souls of the genus: Irano-Turanian taxa colonized the steppes of Eurasia whilst Mediterranean species migrated via eastern and central Mediterranean and North Africa, leaving a trail of species; both pathways ended in the Iberian Peninsula. Our study also confirms that more work is needed to unravel phylogenetic relationships in Rhaponticoides. [ABSTRACT FROM AUTHOR]

A relict endemic species originating from Turkey, Thermopsis turcica, was excluded from Thermopsis in consideration of morphologic studies based on its flowers and fruits as well as micromorphological features that were obtained by scanning electron microscopy (SEM) and data from supporting molecular analyses internal transcribed spacer (ITS). Additionally, phylogenetic analyses (maximum parsimony and neighbour-joining) were conducted using PAUP 4.0 software. These analyses supported a new taxonomical position for the Turkish species. SEM and morphological studies indicated that the species has unique features that have not been observed in other Thermopsideae species. The unique features and characteristics are comprehensively illustrated here. For confirmation of our purpose, the chromosome number and karyotype of V. turcica were determined via the KAMERAM software program. As a result, all detailed examinations and comparisons of Vuralia and related genera suggest that Vuralia is a new monotypic genus within Thermopsideae, and a new genus and combination nova were established for this Turkish species. [ABSTRACT FROM AUTHOR]

Mountains of Anatolia are one of the main Mediterranean biodiversity hotspots and their richness in endemic species amounts for 30% of the flora. Two main factors may account for this high diversity: the complex orography and its role as refugia during past glaciations. We have investigated seven narrow endemics of Centaurea subsection Phalolepis from Anatolia by means of microsatellites and ecological niche modelling (ENM), in order to analyse genetic polymorphisms and getting insights into their speciation. Despite being narrow endemics, all the studied species show moderate to high SSR genetic diversity. Populations are genetically isolated, but exchange of genes probably occurred at glacial maxima (likely through the Anatolian mountain arches as suggested by the ENM). The lack of correlation between genetic clusters and (morpho) species is interpreted as a result of allopatric diversification on the basis of a shared gene pool. As suggested in a former study in Greece, post-glacial isolation in mountains would be the main driver of diversification in these plants; mountains of Anatolia would have acted as plant refugia, allowing the maintenance of high genetic diversity. Ancient gene flow between taxa that became sympatric during glaciations may also have contributed to the high levels of genetic diversity. [ABSTRACT FROM AUTHOR]