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Casearia(Salicaceae) is a pantropical genus of circa 200 species, around half of which dwell in the Neotropics. Despite the availability of phylogenetic studies that suggest that Caseariasensu Sleumer is not monophyletic, a strong phylogenetic framework was still lacking for this genus. We tested the monophyly of Caseariaand examined the relationships of its species to other taxa of the tribe Samydeae, including Laetia, Samydaand Zuelania, which recently have been sunk into Casearia, as well as Euceraea, Lunania, Neoptychocarpus, Ryaniaand Tetrathylacium. We further put a focus on the Neotropical taxa since Caseariaand allies are speciose both on the Caribbean islands and adjacent mainlands, thus providing an interesting group to address the origin of the Caribbean and Cuban flora. Our phylogenetic analyses based on four combined rapidly evolving plastid regions (petD, rpl16, rps4‐trnT‐L‐F, trnK‐matK‐psbA) as well as nuclear ITS revealed Caseariaas monophyletic with high support, including not only the former members of Laetia, Samydaand Zuelaniabut also Euceraeaand Neoptychocarpus. Caseariais constituted by several major clades, mostly being entirely Neotropical, one of which exclusively comprises species endemic to the Caribbean islands. Another clade, which includes all Palaeotropical species, is nested among Neotropical lineages. Our divergence date estimates using the plastid dataset and fossil calibration points in Salicaceae indicate that the Caseariacrown group started to diversify during the late Eocene, approximately 39 Ma. The stem of the Old World clade diverged from Neotropical ancestors around 27 Ma, in the Oligocene. We used BayesTraits to reconstruct the evolution of seven characters commonly used to define Caseariaand allied genera. We found morphological characters, such as branched inflorescences (fasciculate, glomerulous, cymose) or uniseriate stamen series, that work well to circumscribe the genus, whereas dioecy, which was used to diagnose Neoptychocarpus, or higher stamen numbers (>12), found in Laetiaand Zuelania, are homoplastic in Salicaceae, the latter character derived within Caseariafrom ancestors with 7–12 stamens. Pellucid dots appear to have evolved earlier than the divergence of the Caseariaclade in Samydeae, and were lost in Ryaniaand Tetrathylacium, and thus are no synapomorphy for Casearia. In order to establish a monophyletic genus concept for Casearia, we propose to also merge Euceraeaand Neoptychocarpus.Our reconstruction of ancestral areas using BioGeoBears indicate that South America is the ancestral area of Casearia. From there, multiple migrations occurred to Mesoamerica and the Caribbean islands. The Caribbean that comprises nearly all Caribbean endemics started to diversify around 9.5 Ma. Our trees depict C. corymbosa, which exhibits significant infraspecific phylogenetic structure for the sampled Mexican and Colombian individuals, as the sister to the Caribbean clade. The other clade, with Cuban endemics (C. ternstroemioides) but also Mesoamerican and South American taxa, is not sufficiently resolved internally, to allow biogeographic conclusions. The Old World clade of Caseariaprovides another example for a late Laurasian migration starting in the Neotropics.

Jurinea(Asteraceae: Cardueae) is a large Eurasian genus of about 180 species with centres of diversity in Central and Southwest Asia and the eastern Mediterranean. The genus includes many species with adaptations to xero‐ and chasmophytic habitats and comprises numerous endemics, especially in the Caucasus. Generic delimitations between Jurineaand closely related genera have been difficult to assess, as have the phylogenetic relationships with the genera Himalaiella, Jurinellaand Lipschitziella, each of which has been suggested as congeneric with Jurinea. A molecular phylogenetic investigation at both the specific and the generic level to establish the generic delimitation of Jurineaand to evaluate the intergeneric relationships of the genus with other members of the Cardueae was hitherto lacking. In this study, we reconstruct the phylogenetic relationships between Jurineaand several closely related genera based on a representative taxon sampling using DNA sequence data of nuclear (ITS, ETS) and plastid DNA regions (trnK/matK, trnL‐F). We also evaluate the infrageneric classification of Jurinea. Our results indicate that Jurineais polyphyletic in its current circumscription, as the species J. gedrosiacaand J. cartilagineaare placed within the subtribe Centaureineae of the Cardueae. The rest of Jurineais monophyletic and split into two major clades corresponding to the western and eastern range of the distribution area of the genus. The sister clade of Jurineais composed of Himalaiellaand Lipschitziella. Jurinella, which was segregated from Jurineabased on achene morphology, is congeneric with Jurinea. Like in other speciose Eurasian genera, the currently recognised sections do not reflect natural groups, whereas most clades found through molecular phylogenetic inference correlate with geographic patterns. A clade that exclusively comprises Caucasian endemics, including the narrow endemics of J. sect. Neobellae, was found. This clade represents an interesting study group for possible radiation events of Jurineain the Caucasus.

Iresineis a neotropical genus of the Amaranthaceae with most of the species diversity in Mexico and Mesoamerica. It has suffered a complex classification history with considerably diverging views on the genus concept. We have carried out a phylogenetic analysis of Iresineand allied genera using sequence data of combined plastid introns (including the matKCDS) and spacers as well as ITS, and a dense sampling of species. Trees depict a clade of Iresinewith Irenellaand Woehleriadeeply nested. This clade is sister to the remainder of Gomphrenoideae including Hebantheand Trommsdorffia(= Pedersenia). One of two maximally supported subclades of Iresinecomprises mostly species restricted to the Mexican highlands and adjacent areas, whereas the other subclade is composed of more widespread Mexican-Mesoamerican taxa. Pollen grains of Iresineand relatives were examined using high-resolution SEM, which yielded a matrix of 15 pollen characters. Ancestral character state reconstruction shows dodecahedral grains (in I. angustifoliaand I. nigra) to have evolved within the Iresineclade, not involving the complete suite of character shifts associated with metareticulate pollen but just an increase of aperture diameter and a slight decrease of mesoporia width. To the contrary, four character state transformations occurred in the common ancestor of core Gomphrenoideae that led to metareticulate pollen (shifts to a distal orientation of punctae and microspines, to a sunken position of apertures relative to the distal part of mesoporia resulting in narrow mesoporia higher then wide, and a reduction in the diameter of mesoporia). The Iresineclade is characterized by pollen with well-separated ektexinous aperture membrane bodies, rounded or triangular, and gradually tapering into a single spine. For the monophyletic genus Iresine, 35 species are currently accepted. We provide a taxonomic backbone (including one new combination, one new name and several lectotypifications) that also comments on the current understanding of species delimitation.

Limonium(Plumbaginaceae) is a nearly cosmopolitan halophytic genus with ca. 350 species, a large number of which occurs in the Mediterranean region. We have generated a sequence dataset of several plastid (trnKintron including the matKgene, petDintron with the petB-petDspacer, trnLintron with the trnL-trnFspacer) and one nuclear region (nrITS), spanning the major lineages within the genus (102 accessions representing 76 species of Limonium) and related genera. Bayesian inference, maximum likelihood and maximum parsimony analyses converge on a Limoniumclade that includes the genera Afrolimon, Eremolimonand Linczevskia. Plastid and nuclear trees congruently depict a number of major clades, most of them with a characteristic vegetative morphology and growing in specific habitats. Although the position of Afrolimonis incongruently resolved as the sister of a subclade comprising Limonium vulgareand relatives in the plastid trees versus being the sister to a Limonium sogdianum–L. bellidifolium–L. aureumclade in the nrITS tree, both genomic compartments show that Afrolimonis deeply nested in Limonium. Eremolimonis resolved as a close relative of L. sogdianumand L. ferganensebased on plastid and nuclear genomic compartments. Our phylogenetic analysis resulted in an improved picture of internal relationships. Apart from the monophyletic subgenera Limoniumsubg. Limoniumand L.subg.Pteroclados, nine well-supported clades of L.subg. Limoniumare evident, several of which are predominantly constituted by species of a certain geographic range. A subclade of Irano-Turanian species (L. iranicum, L. suffruticosumand relatives) is shown to be unrelated to a L. axillaresubclade, indicating an independent origin of the woody habit in these two lineages. Limoniumsect. Iranolimonsect. nov. is described for the Irano-Turanian woody lineage. The new combination L.sect. Circinariacomb. nov., is established for taxa sometimes included in Afrolimon.