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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.

It is time to synthesize the knowledge that has been generated through more than 260 years of botanical exploration, taxonomic and, more recently, phylogenetic research throughout the world. The adoption of an updated Global Strategy for Plant Conservation (GSPC) in 2011 provided the essential impetus for the development of the World Flora Online (WFO) project. The project represents an international, coordinated effort by the botanical community to achieve GSPC Target 1, an electronic Flora of all plants. It will be a first‐ever unique and authoritative global source of information on the world's plant diversity, compiled, curated, moderated and updated by an expert and specialist‐based community (Taxonomic Expert Networks – “TENs” – covering a taxonomic group such as family or order) and actively managed by those who have compiled and contributed the data it includes. Full credit and acknowledgement will be given to the original sources, allowing users to refer back to the primary data. A strength of the project is that it is led and endorsed by a global consortium of more than 40 leading botanical institutions worldwide. A first milestone for producing the World Flora Online is to be accomplished by the end of 2020, but the WFO Consortium is committed to continuing the WFO programme beyond 2020 when it will develop its full impact as the authoritative source of information on the world's plant biodiversity.

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.

Sequence data from the matKgene, the trnKgroup II intron, the trnLgroup I intron and the trnL-Fspacer were analysed for a broad sampling of the rosids and other eudicots. For the first time all putative genera of Dipentodontaceae and Tapisciaceae (Dipentodon, Huertea, Perrottetia, Tapiscia), as well as the recently described Gerrardinaceae were included in a molecular phylogenetic dataset. All genera were found in a well supported Huerteales clade. Moreover, with the rapidly evolving and non-coding plastid sequence data we were able to resolve the Huerteales clade to branch after Sapindales, and to be sister to a Brassicales-Malvales clade. Increased resolution and support among the malvids underscore the potential of plastid introns and spacers as well as the matKgene as phylogenetic markers in rosids.

The Amaranthaceae is a family within the order Caryophyllales and comprises approx. 800 species in about 70 genera. A representative selection of 130 species from 67 genera was studied. The pollen was found to be generally pantoporate. High resolution scanning electron microscopy and additional light microscopy revealed many new characters of the apertures, in particular of the ektexinous bodies on the aperture membrane, of the exine microsculpture, of the wall ultrastructure, and information on pollenkitt. The subsequent analysis of the resulting large data set led to the recognition of 17 well defined pollen types. The taxonomic distribution of pollen characters in the Amaranthaceae indicates that pollen morphology is informative at different taxonomic levels. Certain pollen characters can be used to circumscribe genera or groups of genera, and often also to distinguish species. Unique within the angiosperms are the hook-shaped, stellately arranged ektexinous bodies covering the pore membranes in pollen of nine genera. Palynological data support the basic subdivision of the Amaranthaceae into the Amaranthoideae and Gomphrenoideae, but indicate that the commonly accepted tribes and subtribes in the classification of Schinz are largely polyphyletic. Pollen characters further provide evidence that a previously described pollination syndrome involving betalains as optical attractants is derived within the Amaranthaceae.

In a palynological study of the Amaranthaceae, a peculiar type of reticulate pollen was found that is characterized by the presence of a porate aperture in each of the meshes of the reticulum. Previously, this type of pollen has been described as “reticulate”;. However, closer investigations show that the reticulum in pollen of Amaranthaceae is composed of mesoporia and pores. Consequently, this kind of reticulum represents a fundamentally different type, and is not homologous to the well known examples of pollen grains with a true reticulum (e.g. in Bromeliaceae, Lamiaceae). Therefore, the term “metareticulate”; is proposed (i.e., pantoporate pollen with a reticulum-like structure of mesoporia and pores). The new term allows to distinguish between metareticulate and truely reticulate pollen, what is important in phylogenetic studies. Metareticulate pollen occurs only within lineages characterized by pantoporate pollen, and is found to be derived from pantoporate pollen in a cladistic analysis. Apart from the Amaranthaceae, metareticulate pollen evolved parallel in Vivianiaceae and Zygophyllaceae. In Caryophyllaceae and Convolvulaceae only a trend towards a metareticulation is observed. Metareticulate pollen is suggested as representing the highest developmental level in successiformy, which is one of the major patterns in pollen evolution leading from tricolpate to pantoporate grains.

With the present study we attempt to elucidate the history of the order Nymphaeales—water-lilies and relatives—in time and space. On the basis of a dense taxon sampling that covers all genera of Cabombaceae and Nymphaeaceae and all subgenera of the genus Nymphaea, and on the basis of well-supported phylogenetic hypotheses, we estimate divergence times in Nymphaeales. Distribution data for all species are used to reconstruct ancestral ranges and to identify possible dispersal events in the biogeographic history of Nymphaeales. Considering the fossil record for the clade as well as geologic history, a plausible historical scenario can be drawn. The assessment of extant biogeography shows that there are several centres of species diversity for Nymphaeales, i.e., northern South America, Central America, the Zambezian region of Africa and northern Australia. However, the diversification of the Nymphaeales started in the Northern Hemisphere when the northern landmasses were covered by tropical vegetation, except for the very high latitudes. The estimation of divergence times depicted two distinct radiation events, a rapid first differentiation into three major lineages during the Paleocene (Cabombaceae, Nuphar, remaining Nymphaeaceae) and the radiation of core Nymphaeaceae (Victoria, Euryale, Nymphaeaincl. Ondinea) from the Late Oligocene to Middle Miocene. The second radiation probably started in the Northern Hemisphere. We hypothesize that subsequent spatial separation and southward relocation of the descendants led to the disjunct distribution of extant sister lineages in core Nymphaeaceae, e.g., Euryale-Victoriaor Nymphaeasubgg. Hydrocallisand Lotos.

The Nymphaeales (water lilies) clade has diverged as the second branch in the tree of angiosperms and is composed of the three families Cabombaceae, Nymphaeaceae and Hydatellaceae. Extant species diversity is constituted by 82 species, about half of which belong to the nearly globally distributed genus Nymphaea. DNA sequence datasets of multiple non-coding and rapidly evolving regions from all three genomic compartments (ca. 8 kb of sequence per taxon) for a dense sampling of Nymphaeales, Austrobaileyales and Amborellawere examined. In an attempt to review the literature on water lilies of the past decades a matrix comprising 62 morphological characters was generated. The crown group of extant Nymphaeales is supported by a series of synapomorphies, several of which have evolved in line with the acquisition of herbaceous habits and adaptations to an aquatic lifestyle such as the loss of cambium and sclerenchyma. Further innovations evolved subsequently within the diversification of the water lily crown group such as hydropotes, or an aril as floating device for the seeds in core Nymphaeaceae that have evolved fruits ripening under water. Both Hydatellaceae and Cabombaceae exhibit many derived features that in part may be explained as adaptations to anemophily. The Nymphaeaceae are supported as monophyletic by most character partitions, including morphology, as are Nupharand Barclayaas successive sisters to the core Nymphaeacae (Nymphaea, Ondinea, Euryale, Victoria). Parsimony analysis of the morphological dataset alone yielded a well resolved and statistically supported tree. Ondineaappears as a close relative of the Australian subg. Anecphyaclade within Nymphaeaby all genomic compartments and morphology. Earlier hypotheses of Nymphaea being paraphyletic to the Euryale-Victoriaclade are inferred in nuclear trees, albeit with low support. Different morphological characters equivocally support a position of the Euryale-Victoriaclade as sister to the subg. Hydrocallis-Lotusclade within Nymphaeaor as sister to all species of Nymphaea. The diversification of the water lily clade is further characterized by a trend towards increased complexity in floral architecture.