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Background and Aims The genus Buxus has high levels of endemism in the Caribbean flora with c. 50 taxa. In Cuba, 82% grow on ultramafic substrates and 59% are nickel (Ni)-accumulators or Ni-hyperaccumulators. Hence it is an ideal model group to study if this diversification could be related to the adaptation to ultramafic substrates and to the Ni-hyperaccumulation. Methods We generated a well-resolved molecular phylogeny, including nearly all of the Neotropical and Caribbean Buxus taxa. To obtain robust divergence times we tested for the effect of different calibration scenarios, and we reconstructed ancestral areas and ancestral character states. Phylogenetic trees were examined for trait-independent shifts in diversification rates and we used multi-state models to test for state-dependent speciation and extinction rates. Key Results We found a Caribbean Buxus clade with Mexican ancestors, encompassing three major subclades, which started to radiate during the middle Miocene (13.25 Mya). Other Caribbean islands and northern South America were reached from c. 3 Mya onwards. Conclusions An evolutionary scenario is evident in which Buxus plants able to grow on ultramafic substrates by exaptation became ultramafic substrate endemics and stepwise evolved from Ni tolerance over Ni-accumulation to Ni-hyperaccumulation, which has triggered species diversification of Buxus in Cuba. Storms could have contributed to Cuba acting as a species pump and to reach other Caribbean islands and northern South America.

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.

Premise of research. The Caribbean is an important area of species diversity within the large pantropical genus Phyllanthus. With the goal of illuminating the evolutionary origins of Caribbean Phyl...

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 Casearia sensu Sleumer is not monophyletic, a strong phylogenetic framework was still lacking for this genus. We tested the monophyly of Casearia and examined the relationships of its species to other taxa of the tribe Samydeae, including Laetia, Samyda and Zuelania, which recently have been sunk into Casearia, as well as Euceraea, Lunania, Neoptychocarpus, Ryania and Tetrathylacium. We further put a focus on the Neotropical taxa since Casearia and 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 Casearia as monophyletic with high support, including not only the former members of Laetia, Samyda and Zuelania but also Euceraea and Neoptychocarpus. Casearia is 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 Casearia crown 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 Casearia and 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 Laetia and Zuelania, are homoplastic in Salicaceae, the latter character derived within Casearia from ancestors with 7–12 stamens. Pellucid dots appear to have evolved earlier than the divergence of the Casearia clade in Samydeae, and were lost in Ryania and Tetrathylacium, and thus are no synapomorphy for Casearia. In order to establish a monophyletic genus concept for Casearia, we propose to also merge Euceraea and 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 Casearia provides another example for a late Laurasian migration starting in the Neotropics.

Campanula is one of the species-rich genera of the bellflower family (Campanulaceae), in a wider sense with ∼600 species, growing in a wide range of habitats in the northern hemisphere. The Caucasu...

The origin of Neotropical species diversity is strongly associated with the geological history of South America. Since the Miocene, a number of species radiations across different Neotropical lineages coincided with the rise of the Andes and the formation of the Isthmus of Panama. The species-rich genus Philodendron Schott (Araceae) is widely distributed across Neotropical rainforests, originating in the Late Oligocene and diversifying more intensely from the Miocene onward. It is likely that its diversification process and distribution patterns are associated with recent geological changes in the Americas. To test this hypothesis, we sampled the species diversity of Philodendron across its entire geographic range and used a combination of three non-coding plastid regions (petD, rpl16, and trnK/matK) to obtain a comprehensive time-calibrated phylogeny. We then inferred geographic range evolution and explored the impact of the Andean orogeny on speciation, extinction, and dispersal. The genus Philodendron originated ~29 million years ago (mya) and experienced the earliest diversification events ~25 mya in the Pan-Amazonian rainforests. From the Middle Miocene onward, multiple geographic range expansion events occurred from Amazonia to southeast Brazil and to the area which would become the Chocó and the northern Andes. From the Pliocene onward, Philodendron reached Central America and the Caribbean islands, and Andean lineages recolonized and diversified in Amazonia. In Philodendron, higher diversification rates are found in the adjacent lowland rainforests of the northern Andes compared with other regions in the Neotropics, demonstrating a potential indirect impact of the Andean uplift on species radiations in lowland regions.

PREMISEThe genusGynoxysand relatives form a species-rich lineage of Andean shrubs and trees with low genetic distances within the sunflower subtribe Tussilaginineae. Previous molecular phylogenetic investigations of the Tussilaginineae have included few, if any, representatives of this Gynoxoid group or reconstructed ambiguous patterns of relationships for it.METHODSWe sequenced complete plastid genomes of 21 species of the Gynoxoid group and related Tussilaginineae and conducted detailed comparisons of the phylogenetic relationships supported by the gene, intron, and intergenic spacer partitions of these genomes. We also evaluated the impact of manual, motif-based adjustments of automatic DNA sequence alignments on phylogenetic tree inference.RESULTSOur results indicate that the inclusion of all plastid genome partitions is needed to infer fully resolved phylogenetic trees of the Gynoxoid group. Whole plastome-based tree inference suggests that the generaGynoxysandNordenstamiaare polyphyletic and form the core clade of the Gynoxoid group. This clade is sister to a clade ofAequatoriumandParagynoxysand also includes some but not all representatives ofParacalia.CONCLUSIONSThe concatenation and combined analysis of all plastid genome partitions and the construction of manually curated, motif-based DNA sequence alignments are found to be instrumental in the recovery of strongly supported relationships of the Gynoxoid group. We demonstrate that the correct assessment of homology in genome-level plastid sequence datasets is crucial for subsequent phylogeny reconstruction and that the manual post-processing of multiple sequence alignments improves the reliability of such reconstructions amid low genetic distances between taxa.

The circumscription of Rondeletieae has changed considerably over time. Historically, 85 genera have been included, characterized by small trees, imbricate corolla aestivation and capsules. Molecular studies led to a narrower circumscription and stressed out that Rondeletieae is mainly an Antillean clade. As historically circumscribed, Rondeletieae is both polyphyletic (involving several tribes, including Condamineae, Sipaneeae, etc.) and paraphyletic with respect to Guettardeae. Uncertainties persist on the tribal circumscription, and its generic limits and relationships. We report results of phylogenetic analyses under parsimony, maximum likelihood and Bayesian analyses including 179 taxa, using concatenated datasets of three chloroplast DNA regions (petD, trnL–F and trnK–matK), their DNA microstructural characters as well as morphology. Our objectives are to: test the monophyly of Rondeletieae and evaluate phylogenetic relationships, evaluate potential characters for tribal and generic delimitation and propose a circumscription for Rondeletieae according to phylogenetic hypothesis using morphological characters. The tribes Guettardeae and Rondeletieae are strongly supported as sister: quincuncial aestivation and spathulate corolla lobes are proposed as a unique combination of characters supporting this relationship. We did not find synapomorphies for each tribe, but there is a set of character combinations that allows distinguishing both tribes that includes the corolla and pollen ornamentation as well as fruit and seed morphology. After evaluating other genera not included in the phylogenies, our proposal is that Rondeletieae contains approximately 120 species in 20 neotropical genera: Acrosynanthus, Acunaeanthus, Blepharidium, Donnellyanthus, Mazaea, Phyllomelia, Rachicallis, Roigella, Rondeletia, Rovaeanthus, Suberanthus, Tainus, plus one tentatively included and recently described (Jamaicanthus).

Thomas Borsch, Hilda Flores-Olvera, Silvia Zumaya, Kai Müller (2018): Pollen characters and DNA sequence data converge on a monophyletic genus Iresine (Amaranthaceae, Caryophyllales) and help to elucidate its species diversity. Taxon 67 (5): 944-976, DOI: https://doi.org/10.12705/675.7

Background and Aims: Many African genera of the Amaranthaceae exhibit unique inflorescences that include sterile flowers modified to hooks or spines. Considering that the abundance of large terrestrial herbivores increased on the African continent with the expansion of grassland and savannah ecosystems, modified sterile flowers could have been an innovation that boosted the diversification of an African achyranthoid clade of Amaranthaceae, with large animals serving dispersal. Methods: We generated an extensively sampled phylogeny comprising 26 of the 31 achyranthoid genera as well as representatives of all other lineages of Amaranthaceae. Phylogenetic tree inference employed four genomic regions, using parsimony, likelihood and Bayesian inference methods. We estimated divergence times, evaluated trait-dependant changes and species diversification rates using state-dependent speciation and extinction models, and reconstructed ancestral character states for modified sterile flowers. Key Results: The achyranthoids were found to be a major clade of the Amaranthaceae, comprising mostly African members. Phylogenetic relationships within this clade were well resolved and supported two main subclades. Several genera were found to be polyphyletic. Our results indicate that the achyranthoids started to diversify ~28 million years ago, and that modified sterile flowers evolved multiple times. An asymmetry in transition rates towards the gain of sterile flowers was observed, whereas no trait-dependent increase in species diversification rates was detected. Bayesian rate heterogeneity analyses indicated that the achyranthoids diversified without significant rate shifts. Conclusions: The accumulation of modified sterile flowers within achyranthoids appears to result from the higher transition rates in favour of modified sterile flowers. Multiple gains suggest an adaptive value for this trait. However, epizoochory does not appear to fuel species diversification, possibly due to extensive gene flow through regularly migrating mammals, which limits the possibility of speciation by isolation.

With approximately 25 endemic species, the genus Pyrus (pears) is highly diverse in the Caucasus ecoregion. The majority of Caucasian pears inhabit xerophytic open woodlands or similar habitats, to which they display morphological adaptations, such as narrow leaves. The other species, both Caucasian and non-Caucasian taxa, mainly inhabit mesophytic forests and display broad leaves. Using a representative taxon sampling of Pyrus from the Caucasus, Europe and Asia, we reconstruct phylogenetic relationships in the genus based on multiple plastid regions. We also estimate the divergence times of major clades in Pyrus, reconstruct the evolution of leaf shapes, and discuss the emergence of xeromorphic leaf traits. Our results confirm the monophyly of Pyrus and the existence of two major clades: (a) an E Asian clade with a crown group age of 15.7 (24.02–8.37 95% HPD) My, and (b) a W Eurasian clade that comprises species from Europe, SW Asia and the Caucasus and that displays a slightly younger crown group of 12.38 (19.02–6.41 95% HPD) My. The existing infrageneric classification of Pyrus was found partially incongruent with the inferred phylogenetic trees. Several currently accepted species were not recovered as monophyletic, indicating that current species limits require re-evaluation. Ancestral character state reconstructions revealed several independent transitions from broad- to narrow-shaped leaves in Pyrus, probably via intermediate-shaped leaves.

Knowledge of within-species genetic diversity can improve effectiveness of conservation measures. These include the mitigation of extinction risks caused by habitat fragmentation, environmental change or diseases as well as site selection for in situ conservation that considers a thorough representation of genotypes. Based on genotyping at twelve nuclear microsatellites we assess genetic diversity of the endangered grassland species Arnica montana . In addition to presenting large scale patterns of genetic diversity, we studied differentiation and inbreeding along altitudinal and latitudinal gradients as well as in relation to population size. Thirty populations (561 individuals) were sampled to represent the species through Central Europe. A broad range of genetic diversity ( H e ) from 0.383 to 0.662 and high levels of genetic differentiation ( F ST = 0.27) were detected. Most variation was found within populations (73%) and not among populations (27%). The majority of populations showed private alleles and a significant pattern of isolation-by-distance. Bayesian analyses of shared ancestry revealed a high number of 24 distinct clusters. Populations at low altitude showed signs of genetic erosion and a tendency for increased clonal reproduction. The strong genetic differentiation of A. montana suggests restricted gene flow among populations. Due to high genetic diversity and no inbreeding, the southern and higher altitude populations in the Alps seem genetically unaffected from genetic erosion despite strong genetic differentiation. The results indicate that in particular lowland populations will depend on human intervention such as assisted gene flow and population reinforcement to avoid further genetic erosion.

The plastid genomes of early-diverging angiosperms were among the first land plant plastomes investigated. Despite their importance to understanding angiosperm evolution, no investigation has so far compared gene content or gene synteny of these plastid genomes with a focus on the Nymphaeales. Here, we report an evaluation and comparison of gene content, gene synteny and inverted repeat length for a set of 15 plastid genomes of early-diverging angiosperms. Seven plastid genomes of the Nymphaeales were newly sequenced for this investigation. We compare gene order and inverted repeat (IR) length across all genomes, review the gene annotations of previously published genomes, generate a multi-gene alignment of 77 plastid-encoded genes and reconstruct the phylogenetic relationships of the taxa under study. Our results show that gene content and synteny are highly conserved across early-diverging angiosperms: All species analyzed display complete gene synteny when accounting for expansions and contractions of the IRs. This conservation was initially obscured by ambiguous and potentially incorrect gene annotations in previously published genomes. We also report the presence of intact open reading frames across all taxa analyzed. The multi-gene phylogeny displays maximum support for the families Cabombaceae and Hydatellaceae, but no support for a clade of all Nymphaeaceae. It further indicates that the genus Victoria is embedded within Nymphaea. Plastid genomes of Trithuria were found to deviate by numerous substitutions and length changes in the IRs. Phylogenetic analyses further indicate that a previously published plastome named Nymphaea mexicana falls into a clade of N. odorata and should be re-evaluated.

We aimed to (i) assess the extant genetic diversity of the riparian relict tree Pterocarya fraxinifolia across its current distribution range in the South Caucasus, including the past refugial areas Colchis and Hyrcan, and (ii) test if a separation of these areas is reflected in its phylogeographic history. Genetic diversity of natural populations was examined using nuclear microsatellite and plastid DNA markers. Spatial genetic structure was evaluated using Bayesian clustering methods and the reconstruction of plastid DNA networks. Divergence times of Colchic and Hyrcanian populations were estimated via divergence dating using a relaxed molecular clock. Allelic richness, private allelic richness, and expected heterozygosity were significantly higher in Hyrcan than in Colchis and the Greater Caucasus, and significant genetic differentiation was revealed between the two groups. Whereas only two plastid haplotypes were detected for the Colchic and Caucasian populations, the Hyrcanian populations displayed 1...

Two well-defined new species of Iresine from Mexico are described based on character data covering vegetative and floral morphology, pollen, and sequences of plastid matK-trnK, trnL-F and rpl16 as well as nuclear ITS. We provide morphological and molecular descriptions, as well as a discussion on diagnostic characters and taxonomic affinities. Both species are distributed in cloud forests; I. borschii is known only from two collections in Veracruz, whereas I. sousae has been collected several times in Oaxaca and Chiapas. Both species are illustrated from herbarium specimens to facilitate their recognition. New field collections and observations are needed to improve our knowledge on the habitat and conservation status of these new species. Citation: Flores-Olvera H., Zumaya S. & Borsch T. 2016: Two new species of Iresine (Amaranthaceae: Gomphrenoideae) from Mexico supported by morphological and molecular characters. — Willdenowia 46: 165–174. doi: http://dx.doi.org/10.3372/wi.46.46113 Version of...

UNLABELLED • PREMISE OF THE STUDY The Caucasus represents one of the world's biodiversity hotspots and includes the climatic refugia Hyrcan on the southern coast of the Caspian Sea and Colchis on the eastern coast of the Black Sea, where different species survived during the Quaternary climatic oscillations. We evaluated the genetic diversity of the relict tree Zelkova carpinifolia shared between the two refugia and distributed throughout the Caucasus and adjacent areas.• METHODS Specimens were collected from 30 geographical sites in Azerbaijan, Georgia, Iran, and Turkey and screened for variability at eight nuclear microsatellite loci. The genetic diversity among and within populations was assessed using a set of statistical measures.• KEY RESULTS We detected 379 different genotypes from a total of 495 individuals with varying degrees of clonal reproduction at the different sites. Low to intermediate levels of genetic diversity were observed at all sites, and strong differentiation between sampling sites was absent. In addition, we observed no clear genetic differentiation between the Colchis and Hyrcan. Bayesian clustering of the genotypes revealed three populations with high levels of admixture between the sampling sites.• CONCLUSIONS The lack of strong genetic structure of studied populations of Z. carpinifolia contrasts with a previous study based on chloroplast markers and suggests that long-distance pollen dispersal is an important factor of gene flow among populations of Z. carpinifolia. The present study does not reveal any particular site with particularly isolated genotypes that would deserve more attention for conservation purposes than others, although some sites should be considered for further investigation.

The genus Tamarix (Tamaricaceae) is a lineage of shrubs and trees with leaves reduced to scales and numerous species adapted to moist and often saline soils in arid and semi-arid climates. Extensive morphological variation and hybridization complicate species delimitation and identification. Based on both morphological and DNA sequence characters, Tamarix humboldtiana Akhani, Borsch & N. Samadi is described as a new species from S Iran. Phylogenetic analysis of plastid rpl16 intron and trnG-trnS spacer sequences depicts a sister group relationship of its unique plastid haplotype to T. tetrandra, whereas nuclear ITS sequence data show close affinities to T. kotschyi. The new species differs from T. kotschyi by distinctly pedicellate, 5-merous flowers and vaginate-amplexicaul leaves. The stem and foliar anatomy and the epidermal micromorphology provide additional characters differentiating the new species from T. kotschyi. The gametic chromosome number of n = 12 reflects that of most of other species of the genus. Tamarix humboldtiana is a rare species living at freshwater riversides in S Iran and is according to current knowledge critically endangered.

Forests of SW Ethiopia constitute the native habitat of Coffea arabica and also the place where domestication of Arabica coffee started. Selection from wild populations has led to numerous landraces (farmer’s varieties) and cultivars. Inter-simple sequence repeats (ISSRs) were generated from a representative set of forest coffee populations and landraces across Ethiopia. For the broad diversity assessment, nine di- and tri-nucleotide ISSR primers were applied, as chosen from a total of 102 primers tested initially. Tetranucleotide ISSR primers differed in amplifying fingerprints that could hardly be analysed due to excessive variation. Tree building analysis (NJ, UPGMA) of 84 polymorphic loci amplified for 125 C. arabica individuals provided evidence for several groups of related genotypes occurring in certain geographical areas of Ethiopia and underscored the existence of wild coffee distinct from landraces. Landraces seem to have originated in different geographical areas of Ethiopia in a stepwise domestication process. While the overall geographical signal in the dataset was weak, analysis in a Bayesian framework using the admixture model with geographical priors in STRUCTURE recovered some genetic clustering. Based on Shannon’s diversity index, populations from Yayu (0.47) and Bonga (0.46) showed highest diversity, followed by individuals from Berhane Kontir (0.41). A likely scenario for the differentiation of C. arabica after an allopolyploidization event is that the hierarchical-geographical patterning of wild Coffea genotypes expected from stepwise range extension was obscured by recent or ancient gene flow. The diversity and geographical distribution of autochthonous C. arabica genotypes indicates the need for a multi-site in situ conservation approach.

Gonzalez Gutierrez P. A., Kohler E. & Borsch T.: New species of Buxus (Buxaceae) from northeastern Cuba based on morphological and molecular characters, including some comments on molecular diagnosis [Novitiae florae cubensis 40], — Willdenowia 43: 125–137. June 2013. — Online ISSN 1868-6397; © 2013 BGBM Berlin-Dahlem.. Stable URL: http://dx.doi.org/10.3372/wi.43.43115 Three new species of Buxus endemic to the serpentine areas of Sierra de Nipe and Sierra del Cristal, northeastern Cuba, are described. Morphological descriptions including pollen and leaf anatomy are provided as well as sequences of the plastid trnK-matK and trnL-trnF regions, serving as molecular descriptions. The substitutions were evaluated to find suitable characters for a molecular diagnosis that complements the morphological diagnosis. Using the newly described species of Buxus as an example, prospects and pitfalls of DNA characters to support species diagnosis are discussed. Furthermore, an assessment of the distribution, ha...

Iresine rzedowskii Zumaya, Flores Olv. & Borsch and I. valdesii Zumaya, Flores Olv. & Borsch are described, illustrated, and compared to morphologically similar species. In addition, pollen SEM micrographs and distribution maps are provided for the new species. Iresine rzedowskii is a shrub with long clambering stems, the younger ones reddish with conspicuous lenticels and the older ones with suberose cortex. It is the only species of Iresine that has pollen grains with a foveolate tectum. Iresine valdesii is also a shrub but with stiff erect branching and small, perennial coriaceous leaves. The synflorescences of staminate plants are solitary, very small, usually once-branched thyreoid structures while those of pistillate plants are very different, with paracladia appearing terminal on most branches and erect, up to 13 cm long, and two to three times branched. Both species are restricted to Mexico. Iresine rzedowskii ranges from northwestern Chihuahua to northern Oaxaca, while I. valdesii is end...

Fil: Arias, Salvador. Universidad Nacional Autónoma de México; México Fil: Berendsohn, Walter G.. Freie Universität Berlin; Alemania Fil: Borsch, Thomas. Freie Universität Berlin; Alemania Fil: Flores Olvera, Hilda. Universidad Nacional Autónoma de México; México Fil: Ochoterena, Helga. Universidad Nacional Autónoma de México; México Fil: von Mering, Sabine. Freie Universität Berlin; Alemania Fil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

Fuentes-Bazan S., Uotila P. & Borsch T.: A novel phylogeny-based generic classification for Chenopodium sensu lato, and a tribal rearrangement of Chenopodioideae (Chenopodiaceae). — Willdenowia 42: 5–24. June 2012. — On-line ISSN 1868-6397; © 2012 BGBM Berlin-Dahlem. Stable URL: http://dx.doi.org/10.3372/wi.42.42101 Molecular phylogenetic analysis of the subfamily Chenopodioideae of the goosefoot family (Chenopodiaceae), with the addition of matK/trnK sequences to an existing trnL-F data set, indicates that Chenopodium as traditionally recognised consists of six independent lineages. One of these, the Dysphania-Teloxys clade, had already been recognised previously as a separate tribe Dysphanieae. Of the five others, Chenopodium is here re-defined in a narrow sense so as to be monophyletic. The C. polyspermum, C. rubrum and C. murale clades are successive sisters of a lineage constituted by Atripliceae s.str. plus Chenopodium s.str. Consequently, the long forgotten genera Lipandra (for C. polysper...

Alternanthera (Amaranthaceae) is a diverse genus (80–200 species) largely restricted to the American Tropics. With Pedersenia and Tidestromia, it makes up the ‘Alternantheroid clade’ in Gomphrenoideae. Parsimony and Bayesian analyses of nucleotide sequences of nuclear (ITS) and plastid (rpl16, trnL-F) and morphological characters identify that the capitate stigma of Alternanthera is a synapomorpy within the Alternantheroids. Within Alternanthera, two major clades were resolved, both of which were marked by otherwise homoplasious characters of the gynoecium: Clade A [99% jackknife (JK); 1.0 posterior probability (PP)] with nine species and Clade B (60% JK; 0.98 PP) with 22 species. Four subclades (B1–B4), strongly supported statistically, were identified in Clade B. Previous subgeneric classifications of Alternanthera appear artificial in light of our new molecular phylogenetic analyses. Most major lineages are congruently resolved by nuclear and plastid data but some incongruence between the nrITS and plastid phylogenetic trees suggests hybridization may have played a role in the rampant speciation in Alternanthera. Whereas C4 photosynthesis appears to have evolved in a single clade, the position of A. littoralis var. maritima (C3) in this clade may be explained by hybrid speciation rather than a reversal from C4 to C3. All C3–C4 intermediates belong to a different clade that also contains C3 species, but species limits, including the widely studied A. tenella, are unclear. The clade including A. tenella and A. halimifolia contains most of the species endemic to the Galapagos whereas A. nesiotes, also endemic to the islands, is nested among widespread American taxa. This suggests that the Galapagos radiation of Alternanthera may have arisen from at least two independent colonization events followed by a subsequent radiation in the former lineage. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 493–517.

Recent phylogenetic analyses revealed a grade with Ranunculales, Sabiales, Proteales, Trochodendrales, and Buxales as first branching eudicots, with the respective positions of Proteales and Sabiales still lacking statistical confidence. As previous analyses of conserved plastid genes remain inconclusive, we aimed to use and evaluate a representative set of plastid introns (group I: trnL; group II: petD, rpl16, trnK) and intergenic spacers (trnL-F, petB-petD, atpB-rbcL, rps3-rpl16) in comparison to the rapidly evolving matK and slowly evolving atpB and rbcL genes. Overall patterns of microstructural mutations converged across genomic regions, underscoring the existence of a general mutational pattern throughout the plastid genome. Phylogenetic signal differed strongly between functionally and structurally different genomic regions and was highest in matK, followed by spacers, then group II and group I introns. The more conserved atpB and rbcL coding regions showed distinctly lower phylogenetic information content. Parsimony, maximum likelihood, and Bayesian phylogenetic analyses based on the combined dataset of non-coding and rapidly evolving regions (>14 000 aligned characters) converged to a backbone topology of eudicots with Ranunculales branching first, a Proteales–Sabiales clade second, followed by Trochodendrales and Buxales. Gunnerales generally appeared as sister to all remaining core eudicots with maximum support. Our results show that a small number of intron and spacer sequences allow similar insights into phylogenetic relationships of eudicots compared to datasets of many combined genes. The non-coding proportion of the plastid genome thus can be considered an important information source for plastid phylogenomics.

Borsch T., Ortuno Limarino T. & Nee M. H.: Phylogenetics of the neotropical liana genus Pedersenia (Amaranthaceae: Gomphrenoideae) and discovery of a new species from Bolivia based on molecules and morphology. — Willdenowia 41: 5–14. — Online ISSN 1868-6397; © 2011 BGBM Berlin-Dahlem. doi:10.3372/wi.41.41101 (available via http://dx.doi.org/) The monophyletic genus Pedersenia comprises eleven species in the Neotropics, one of which, P. volubilis, is here described as new to science, being an endemic of mixed semi-deciduous Bolivian-Tucuman Interandean lower subhumid forest at mid elevations of the Department of Santa Cruz, Bolivia. Among the liana species of Pedersenia, it differs by twining stems, synflorescences constituted by terminal stems of several metres and small, lanceolate leaves. It is also characterised by two synapomorphic substitutions in the matK CDS. Sequence data of trnK/matK show considerable divergence between morphologically very similar liana species of tropical evergreen bro...

The Caryophyllales Network strives to assemble an online dynamic synthesis of the order Caryophyllales, uniting the current knowledge about the phylogeny of the order with up-to-date information on the individual taxa contained. Capturing taxonomic data and the decision processes involved in the definition and circumscription of the taxa requires highly complex specialized software. The Caryophyllales Network uses the EDIT Platform for Cybertaxonomy for that purpose. In the context of the online treatment of the family Nepenthaceae, we describe the steps taken to assemble the database, the interaction with other electronic sources, the links with the World Flora Online initiative, and the prospects for the maintenance and further development of the Nepenthaceae segment of the Caryophyllales database. Nepenthaceae constitute an example of a family with a relatively recent flora treatment (Flora Malesiana, published in 2001), which to a large extent covers its total range of distribution, but with further species subsequently described as new to science in mostly regional treatments, and with an analysis of relationships and species limits on the basis of evolutionary methods just emerging. A snapshot of the current state of the database is provided as an annotated checklist in PDF format in the Supplementary Material online, which includes 176 species and nine naturally occurring named hybrids and treats 435 species and infraspecific names.Citation: Berendsohn W. G., Borsch T., Guntsch A., Kohlbecker A., Korotkova N., Luther K., Muller A., Plitzner P. & Mering S. von 2018: Using the EDIT Platform for Cybertaxonomy to prepare and publish a treatment for the Caryophyllales Network: an online synthesis of the Nepenthaceae. – Willdenowia 48: 335–344. doi: https://doi.org/10.3372/wi.48.48301Version of record first published online on 17 September 2018 ahead of inclusion in December 2018 issue.

Schaferhoff B., Muller K. F. & Borsch T.: Caryophyllales phylogenetics: disentangling Phytolaccaceae and Molluginaceae and description of Microteaceae as a new isolated family. — Willdenowia 39: 209–228. — Online ISSN 1868-6397; © 2009 BGBM Berlin-Dahlem. doi:10.3372/wi.39.39201 (available via http://dx.doi.org/) The Caryophyllales are one of the major lineages of angiosperms, including some 12 000 species and well known families such as Amaranthaceae, Cactaceae, Caryophyllaceae, Droseraceae, Nyctaginaceae and Polygonaceae. Phylogenetic hypotheses based on molecular characters have led to their circumscription and have considerably improved our understanding of interfamilial relationships. For this study, we generated a data set of the non-coding and rapidly evolving chloroplast petB-petD region, consisting of a transcribed spacer and a group II intron for 87 taxa of Caryophyllales and 22 outgroups. In addition, we analysed a complementary matK data set with complete sequences of the coding regio...

Introns and spacers are a rich and well-appreciated information source for evolutionary studies in plants. Compared to coding sequences, the mutational dynamics of introns and spacers is very different, involving frequent microstructural changes in addition to substitutions of individual nucleotides. An understanding of the biology of sequence change is required for correct application of molecular characters in phylogenetic analyses, including homology assessment, alignment coding, and tree inference. The widely used term “indel” is very general, and different kinds of microstructural mutations, such as simple sequence repeats, short tandem repeats, homonucleotide repeats, inversions, inverted repeats, and deletions, need to be distinguished. Noncoding DNA has been indispensable for analyses at the species level because coding sequences usually do not offer sufficient variability. A variety of introns and spacers has been successfully applied for phylogeny inference at deeper levels (major lineages of angiosperms and land plants) in past years, and phylogenetic structure R in intron and spacer data sets usually outperforms that of coding-sequence data sets. In order to fully utilize their potential, the molecular evolution and applicability of the most important noncoding markers (the trnT–trnF region comprising two spacers and a group I intron; the trnS–G region comprising one spacer and a group II intron in trnG; the group II introns in petD, rpl16, rps16, and trnK; and the atpB–rbcL and psbA–trnG spacers) are reviewed. The study argues for the use of noncoding DNA in a spectrum of applications from deep-level phylogenetics to speciation studies and barcoding, and aims at outlining molecular evolutionary principles needed for effective analysis.

A spectrum of eight pharmacologically important secondary compounds, all putatively belonging to the polyketide pathway (hypericin, pseudohypericin, emodin, hyperforin, hyperoside, rutin, quercetin, and quercitrin) were analyzed in several hypericin-producing species of Hypericum by LC-MS/MS. Different organs such as leaves, stems and roots of wild-grown plants of Hypericum hirsutum L., Hypericum maculatum Crantz s. l., Hypericum montanum L., Hypericum tetrapterum Fr. collected in Slovakia and of Hypericum perforatum L. collected in India were examined individually. Highest contents of hypericin, pseudohypericin, and emodin were found in H. montanum, suggesting that there are alternative species to H. perforatum with high pharmaceutical value. Amounts of hyperforin and quercetin were highest in H. perforatum, whereas highest contents of hyperoside and quercitrin were found in H. maculatum. A significant positive correlation between hypericin and pseudohypericin as well as between hypericin and emodin was observed by Kruskal's multidimensional scaling (MDS), indicating a parallel enhancement of emodin as a common precursor in the biosynthetic pathways of hypericin and pseudohypericin. Furthermore, MDS combined with principal component analysis (PCA) revealed strong correlations in the occurrence of pseudohypericin and emodin, pseudohypericin and quercitrin, hypericin and quercitrin, emodin and quercitrin, hyperoside and quercitrin, rutin and quercetin, and, hyperforin and quercetin. On the other hand, rutin showed a negative correlation with emodin as well as with quercitrin. Furthermore, hierarchical agglomerative cluster analysis (HACA) clustered hypericin and pseudohypericin, grouping emodin at equal distance from both. Considerable infraspecific variability in secondary compound spectrum and load of different populations of H. maculatum from Slovakia underscores the need for detailed studies of genotypic variation and environmental factors in relation to polyketide biosynthesis and accumulation.

Lohne C., Wiersema J. H. & Borsch T.: The unusual Ondinea, actually just another Australian water-lily of Nymphaea subg. Anecphya (Nymphaeaceae). — Willdenowia 39: 55–58. — Online ISSN 1868-6397; © 2009 BGBM Berlin-Dahlem. doi:10.3372/wi.39.39104 (available via http://dx.doi.org/) Based on recent findings of phylogenetic studies using character sets from all three genomic compartments and from morphology, Ondinea purpurea is transferred to Nymphaea and the new name N. ondinea is validly published. This change in classification implements the criterion that higher taxa should be monophyletic. Although, compared to other species of Nymphaea, the Australian N. ondinea appears to be phenotypically very different, most shifts in character states that led to its evolution (e.g., loss of perianth in some of the populations, decrease in stamen and carpel number) are rather quantitative. Several characters not only support a position of Ondinea within Nymphaea (such as an eusyncarpous gynoeceum with carpe...

Sequence data from the matK gene, the trnK group II intron, the trnL group I intron and the trnL-F spacer 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 matK gene as phylogenetic markers in rosids.

The Amaranthaceae-Chenopodiaceae alliance has been the focus of several phylogenetic studies, but major questions concerning the internal relationships of Amaranthaceae still remain unanswered. This study aims to test the monophyly of the subfamily Gomphrenoideae and to examine the generic relationships within this group. Parsimony and Bayesian analyses of trnL-F and rpl16 show that the subfamily Gomphrenoideae is monophyletic. The clade of Gomphrenoideae represents a large and diverse radiation of the Amaranthaceae in the New World. Unilocular anthers are a morphological synapomorphy for Gomphrenoideae that was derived from bilocular anthers. Three major clades are resolved: the Gomphrenoids, the Alternantheroids, and the Iresinoids, which are largely supported by pollen morphology. The Iresinoid clade is sister to Alternantheroids plus Gomphrenoids, rendering metareticulate pollen as the synapomorphy for the latter two clades. Tribes and subtribes delimited by androecium and inflorescence characters are poly- or paraphyletic. Several genera are monophyletic including the large genus Alternanthera, whereas Gomphrena is polyphyletic. Irenella and Woehleria are resolved within Iresine whereas Blutaparon and Lithophila fall within the polyphyletic Gomphrena. The trnL-F and rpl16 sequence data are the most variable chloroplast regions examined to date for the family and are highly effective in resolving relationships in Amaranthaceae.

Malpighiales are one of the most diverse orders of angiosperms. Molecular phylogenetic studies based on combined sequences of coding genes allowed to identify major lineages but hitherto were unable to resolve relationships among most families. Spacers and introns of the chloroplast genome have recently been shown to provide strong signal for inferring relationships among major angiosperm lineages and within difficult clades. In this study, we employed sequence data of the petD group II intron and the petB-petD spacer for a set of 64 Malpighiales taxa, representing all major lineages. Celastrales and Oxalidales served as outgroups. Sequence alignment was straightforward due to frequent microstructural changes with easily recognizable motifs (e.g., simple sequence repeats), and well defined mutational hotspots. The secondary structure of the complete petD intron was calculated for Idesia polycarpa as an example. Domains I and IV are the most length variable parts of the intron. They contain terminal A/T-rich stem-loop elements that are suggested to elongate independently in different lineages with a slippage mechanism earlier reported from the P8 stem-loop of the trnL intron. Parsimony and Bayesian analyses of the petD dataset yielded trees largely congruent with results from earlier multigene studies but statistical support of nodes was generally higher. For the first time a deep node of the Malpighiales backbone, a clade comprising Achariaceae, Violaceae, Malesherbiaceae, Turneraceae, Passifloraceae, and a Lacistemataceae–Salicaceae lineage received significant statistical support (83% JK, 1.00 PP) from plastid DNA sequences.

Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersia...

The Nymphaeales (water-lilies and relatives) represent one of the earliest branching lineages of angiosperms and comprise about 70 aquatic species. Here, we present a comprehensive study of phylogenetic relationships within the Nymphaeales from a dataset containing 24 representatives of the order, including all currently recognized genera and all subgenera of the genus Nymphaea, plus 5 outgroup taxa. Nine different regions of the chloroplast genome − comprising spacers, group II introns, a group I intron, and a protein coding gene − were analysed. This resulted in a character matrix of 6597 positions and an additional 369 characters obtained from coded length mutations. Maximum parsimony and Bayesian analyses of the complete dataset yielded congruent, fully resolved and well-supported trees. Our data confirm the monophyly of the Cabombaceae but do not provide convincing support for the monophyly of Nymphaeaceae with respect to Nuphar. Moreover, the genus Nymphaea is inferred to be paraphyletic with respect to Ondinea, Victoria and Euryale. In fact, the Australian endemic Ondinea forms a highly supported clade with members of the Australian Nymphaea subgenus Anecphya. In addition, Victoria and Euryale are inferred to be closely related to a clade comprising all night-blooming water-lilies (Nymphaea subgenera Hydrocallis and Lotos). An experimental approach showed taxon sampling to be of influence on the nodes reconstructed in core Nymphaeaceae. The results underscore that more diverse genera, if not clearly known to be monophyletic, should be represented by all major lineages. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 154, 141–163.

Nuclear holoploid genome sizes (C-values) have been estimated to vary about 800-fold in angiosperms, with the smallest established 1C-value of 157 Mbp recorded in Arabidopsis thaliana. In the highly specialized carnivorous family Lentibulariaceae now three taxa have been found that exhibit significantly lower values: Genlisea margaretae with 63 Mbp, G. aurea with 64 Mbp, and Utricularia gibba with 88 Mbp. The smallest mitotic anaphase chromatids in G. aurea have 2.1 Mbp and are thus of bacterial size (NB: E. coli has ca. 4 Mbp). Several Utricularia species range somewhat lower than A. thaliana or are similar in genome size. The highest 1C-value known from species of Lentibulariaceae was found in Genlisea hispidula with 1510 Mbp, and results in about 24-fold variation for Genlisea and the Lentibulariaceae. Taking into account these new measurements, genome size variation in angiosperms is now almost 2000-fold. Genlisea and Utricularia are plants with terminal positions in the phylogeny of the eudicots, so that the findings are relevant for the understanding of genome miniaturization. Moreover, the Genlisea-Utricularia clade exhibits one of the highest mutational rates in several genomic regions in angiosperms, what may be linked to specialized patterns of genome evolution. Ultrasmall genomes have not been found in Pinguicula, which is the sister group of the Genlisea-Utricularia clade, and which does not show accelerated mutational rates. C-values in Pinguicula varied only 1.7-fold from 487 to 829 Mbp.

Carnivorous plants have emerged as model systems for addressing many ecological and evolutionary questions, and since Lentibulariaceae comprise more than half of all known carnivorous species (325 spp.), they are of particular interest. Studies using various molecular markers have established that Lentibulariaceae and their three genera are monophyletic with Pinguicula being sister to a Genlisea-Utricularia-clade, while the closest relatives of the family remain uncertain. Character states of the carnivorous syndrome in related proto-carnivorous lamialean families apparently emerged independently. In Utricularia, the terrestrial habit has been reconstructed as plesiomorphic, and an extension of subgenus Polypompholyx is warranted. In the protozoan-attracting Genlisea, subgenus Tayloria is revealed as basal lineage. In Pinguicula, the six major lineages found reflect radiations in clearly defined geographic regions, whereas most previously recognized subgeneric taxa are non-monophyletic. Genlisea and Utricularia exhibit substitutional rates that rank among the highest in angiosperms for the molecular markers analyzed. One possible explanation for this lies in selective constraints on a wide range of genomic regions that may have been lowered due to the use of an alternative mode of acquiring nutrients.

Variability of Selaginella megaspore microsculpture is defined and illustrated by means of SEM and TEM. Additional EDX analyses demonstrated that microsculpture elements in the investigated specimens are mainly formed by silica which may be removed by hydrofluoric acid. Our observations suggest that different proportions of sporopollenin/silica are present in the outer coating of at least some Selaginella megaspore walls. Pattern formation mechanisms as well as implications for terminology are discussed. On the basis of this investigation and using data available from the literature, it is argued that the sporoderm layers of Isoetes and Selaginella megaspores are probably homologous, supporting the consensual view.

Stellate pore ornamentation is an unusual feature of angiosperm pollen, so far it is known in only ten genera of Amaranthaceae. The pollen grains of these plants have apertures with large hook‐shaped ektexinous bodies that are stellately arranged. Previous studies interpreted this character complex as a synapomorphy in consideration of its strong specialization. By reconstructing the evolution of stellate pore ornamentation based on phylogenetic trees of Amaranthaceae obtained by parsimony, likelihood, and Bayesian analysis of chloroplast trnK/matK DNA sequences, clear evidence is provided for several independent origins and reversals to less specialized aperture types. In addition to the gomphrenoid genus Pseudoplantago, stellate pore ornamentation evolved several times among achyranthoid genera, which have an African distribution. The most derived apertures, with 5 – 6 large protruding hooks, appear independently in Centemopsis on the one hand, and in Psilotrichum sericeum on the other. In an effort to ...

The genus Pinguicula is one of the three genera of the carnivorous Lentibulariaceae, comprising approximately 80 species. Phylogeny inference using nucleotide sequences of the chloroplast gene matK and the trnK group II intron, as well as a set of 32 morphological characters revealed five well-supported, major lineages within the genus. These lineages largely reflect radiations in clearly defined geographic regions, whereas most previously recognized sections of the genus are shown to be para- or polyphyletic. A species-rich Mexican-Central American-Caribbean clade has the Eurasian P. alpina and an East Asian clade as successive sisters. All three are characterized by a production of flower buds on winter-resting plants, a specific corolla hair structure and a very large corolla lower central lobe. Another diverse clade is composed of species with primarily European distribution including the widespread type species P. vulgaris. For this clade, vegetative reproduction during dormancy is synapomorphic. Species native to SE North America and the South American Andes and a group of Mediterranean and NE Atlantic coast species together appear in a fifth well-supported clade, that is characterized by a tropical-type growth habit. It is the only clade that has reached temperate zones of the southern hemisphere.

DNA sequences of nine genes (plastid: atpB, matK, and rbcL; mitochondrial: atp1, matR, mtSSU, and mtLSU; nuclear: 18S and 26S rDNAs) from 100 species of basal angiosperms and gymnosperms were analyzed using parsimony, Bayesian, and maximum likelihood methods. All of these analyses support the following consensus of relationships among basal angiosperms. First, Amborella, Nymphaeaceae, and Austrobaileyales are strongly supported as a basal grade in the angiosperm phylogeny, with either Amborella or Amborella and Nymphaeales as sister to all other angiosperms. An examination of nucleotide substitution patterns of all nine genes ruled out any possibility of analytical artifacts because of RNA editing and GC-content bias in placing these taxa at the base of the angiosperm phylogeny. Second, Magnoliales are sister to Laurales and Piperales are sister to Canellales. These four orders together constitute the magnoliid clade. Finally, the relationships among Ceratophyllum, Chloranthaceae, monocots, magnoliids, and eudicots are resolved in different ways in various analyses, mostly with low support. Our study indicates caution in total evidence approaches in that some of the genes employed (e.g., mtSSU, mtLSU, and nuclear 26S rDNA) added signal that conflicted with the other genes in resolving certain parts of the phylogenetic tree.

Nymphaea odorata, Nymphaeaceae, is the most widely distributed water-lily in North America. Disagreement exists on whether this morphologically variable species should be split into two species, N. odorata and N. tuberosa, or treated as one species with two subspecies. Morphological characters and markers from the inter-simple sequence repeats (ISSRs) were examined to assess taxonomic status and elucidate patterns of genetic variation among populations. This study provides evidence against treatment of N. tuberosa at species rank. The principal component analysis of 26 vegetative characters underscores immense variability, but does partially segregate populations of subsp. odorata and subsp. tuberosa. Based on analysis of variance, a new set of morphological characters is proposed to distinguish the two subspecies: mean leaf blade length-to-width ratio, petiole striping, and lobe apex shape. Results from ISSRs show high polymorphism within and among populations. Genetic variation was found largely within geographical regions (89%) rather than among regions. Principal coordinate (PCOA) analyses and minimum spanning tree (MST) analyses based on ISSRs clearly distinguished Nymphaea mexicana and N. odorata. Within N. odorata, samples of subsp. odorata appear to be a distinct entity, whereas samples largely but not completely separated from samples of subsp. tuberosa. PCOA and MST showed linkage between most samples of subsp. odorata whereas this was less evident in UPGMA.

Sequence data from the nuclear internal transcribed spacer (ITS) and the plastid trnL-trnF regions were used to assess relationships among populations of N. odorata across its North American range, and to evaluate whether subsp. odorata and subsp. tuberosa form distinct taxonomic units. Nymphaea mexicana was included because of suspected hybridization with N. odorata. The trnL-trnF region provided a single informative site in N. odorata. In contrast, the ITS region was more variable. Phylogenetic analysis of ITS data supports the monophyly of the two species. Within N. odorata, two clades were resolved largely representing subsp. odorata and subsp. tuberosa, although a few individuals appeared outside the respective clades. Polymorphic sites were detected in ITS, indicating possible hybridization between the subspecies. The geographic location of these hybrids suggests a possible hybrid zone. Overall, molecular evidence supports the segregation of subsp. odorata and subsp. tuberosa, with limited gene flow between them.

The bladderworts (Utricularia, Lentibulariaceae) are the most diverse carnivorous plant genus, with a nearly worldwide distribution. In the present study, chloroplast DNA sequences of the trnK intron were used to reconstruct phylogenetic relationships within the genus. Parsimony, likelihood, and Bayesian analyses resulted in highly congruent and well-resolved trees. The phylogenetic signal provided by the noncoding trnK intron partition of the dataset is similar to that of the matK coding region, although the latter is twice as long. Within matK, indels appeared in multiples of three except very close to the 3′ end of the gene. Substitutions were found to result in or eliminate stop codons, thus creating a length variable gene end. Indels in both trnK and matK exhibit low degrees of homoplasy, irrespective of their size. A tree based on indels alone is largely congruent to the substitution-based trees but less resolved. Three major clades found within Utricularia are classified as subgen. Utricularia, subgen. Bivalvia, and subgen. Polypompholyx. The immediate common ancestor of Utricularia is suggested to have been a terrestrial plant whereas epiphytic and aquatic habits evolved later in terminal clades.

Aristolochiaceae, a family of worldwide distribution comprising about 500 species, is a member of Piperales. Although Piperales is clearly monophyletic, the precise relationship within the order is ambiguous due to inconsistent placement of Lactoris fernandeziana. The appearance in some studies of Lactoris within Aristolochiaceae and the incongruence in generic treatments have also raised questions about the infrastructure of the family. This study addresses the overall generic relationships in Aristolochiaceae and its position in Piperales based on dense taxon sampling and sequence data from the plastid trnL-F region. The study resolved Piperales consisting of two major clades (Piperaceae plus Saururaceae and Lactoridaceae plus Aristolochiaceae) and Lactoris nested within Aristolochiaceae but with low support. The concept of two subfamilies in Aristolochiaceae, Asaroideae and Aristolochioideae, gains maximum statistical support. A generic treatment of Aristolochiaceae based on trnL-F is proposed which is congruent with recent analyses based on morphological characters.

Plastid matK gene sequences for 374 genera representing all angiosperm orders and 12 genera of gymnosperms were analyzed using parsimony (MP) and Bayesian inference (BI) approaches. Traditionally, slowly evolving genomic regions have been preferred for deep-level phylogenetic inference in angiosperms. The matK gene evolves approximately three times faster than the widely used plastid genes rbcL and atpB. The MP and BI trees are highly congruent. The robustness of the strict consensus tree supercedes all individual gene analyses and is comparable only to multigene-based phylogenies. Of the 385 nodes resolved, 79% are supported by high jackknife values, averaging 88%. Amborella is sister to the remaining angiosperms, followed by a grade of Nymphaeaceae and Austrobaileyales. Bayesian inference resolves Amborella + Nymphaeaceae as sister to the rest, but with weak (0.42) posterior probability. The MP analysis shows a trichotomy sister to the Austrobaileyales representing eumagnoliids, monocots + Chloranthales, and Ceratophyllum + eudicots. The matK gene produces the highest internal support yet for basal eudicots and, within core eudicots, resolves a crown group comprising Berberidopsidaceae/Aextoxicaceae, Santalales, and Caryophyllales + asterids. Moreover, matK sequences provide good resolution within many angiosperm orders. Combined analyses of matK and other rapidly evolving DNA regions with available multigene data sets have strong potential to enhance resolution and internal support in deep level angiosperm phylogenetics and provide additional insights into angiosperm evolution.

A phylogenetic analysis of Chenopodiaceae and Amaranthaceae was carried out using sequence variation of the chloroplast gene rbcL. Our sampling included 108 species of these two families along with 29 species of Caryophyllales serving as outgroups. Phylogeny inferences with maximum parsimony and maximum likelihood indicate that the two families form a well‐supported monophyletic clade that is sister to Achatocarpaceae. Despite extensive sampling, we found that the relationship between Chenopodiaceae and Amaranthaceae remains unclear as a result of short and weakly supported basal branches. The clearly monophyletic Polycnemoideae (traditionally considered a subfamily of Chenopodiaceae) appear as sister to Amaranthaceae sensu stricto. Within Amaranthaceae, most major lineages inferred except Gomphrenoideae and Celosieae do not correspond to recognized subfamilies and tribes. Bosea and Charpentiera branch first in the Amaranthaceae. Within Chenopodiaceae, the genera of Betoideae occur in basal and largely un...