We present the first large-scale phylogenetic hypothesis for the genus Carex based on 996 of the 1983 accepted species (50.23%). We used a supermatrix approach using three DNA regions: ETS, ITS and matK. Every concatenated sequence was derived from a single specimen. The topology of our phylogenetic reconstruction largely agreed with previous studies. We also gained new insights into the early divergence structure of the two largest clades, core Carex and Vignea clades, challenging some previous evolutionary hypotheses about inflorescence structure. Most sections were recovered as non-monophyletic. Homoplasy of characters traditionally selected as relevant for classification, historical misunderstanding of how morphology varies across Carex, and regional rather than global views of Carex diversity seem to be the main reasons for the high levels of polyphyly and paraphyly in the current infrageneric classification.

Despite previous efforts to unify the terminology for Cyperaceae, two different terms, perigynium and utricle, are in common use for the prophyllar bract enclosing the female flower of Carex. Use of these terms is divided largely on geographic lines (mainly North American versus European and other authors, respectively). The recent merging of Kobresia with Carex requires a single term to refer to both the open prophyll of Kobresia and the laterally closed one of Carex. However, even when authors use utricle for Carex species, these same authors do not refer to the open prophyll of Kobresia as a utricle. We show that perigynium was apparently coined earlier than utricle, at the end of the 18th century, but the term utricle became more widespread than perigynium by the 20th century. Neither of the two terms is unambiguous, as both have also been used for other structures in other plant groups. Given this background, we propose revised definitions of both terms based on two facts: 1) the greater semantic accuracy of perigynium to refer to both the prophylls of Carex and the former genus Kobresia; and 2) the greater spread, and thus social utility, of the term utricle. We also discuss the terminology used for the fertile prophylls of lower branching orders found in some Carex groups and recommend use of the terms cladoprophyll, tubular cladoprophyll, and utriculiform cladoprophyll.

Major public DNA databases — NCBI GenBank, the DNA DataBank of Japan (DDBJ), and the European Molecular Biology Laboratory (EMBL) — are invaluable biodiversity libraries. Systematists and other biodiversity scientists commonly mine these databases for sequence data to use in phylogenetic studies, but such studies generally use only the taxonomic identity of the sequenced tissue, not the specimen identity. Thus studies that use DNA supermatrices to construct phylogenetic trees with species at the tips typically do not take advantage of the fact that for many individuals in the public DNA databases, several DNA regions have been sampled; and for many species, two or more individuals have been sampled. Thus these studies typically do not make full use of the multigene datasets in public DNA databases to test species coherence and select optimal sequences to represent a species. In this study, we introduce a set of tools developed in the R programming language to construct individual-based trees from NCBI GenBank data and present a set of trees for the genus Carex (Cyperaceae) constructed using these methods. For the more than 770 species for which we found sequence data, our approach recovered an average of 1.85 gene regions per specimen, up to seven for some specimens, and more than 450 species represented by two or more specimens. Depending on the subset of genes analyzed, we found up to 42% of species monophyletic. We introduce a simple tree statistic—the Taxonomic Disparity Index (TDI)—to assist in curating specimen-level datasets and provide code for selecting maximally informative (or, conversely, minimally misleading) sequences as species exemplars. While tailored to the Carex dataset, the approach and code presented in this paper can readily be generalized to constructing individual-level trees from large amounts of data for any species group.

We undertook a three-year collaboration with two area schools to generate novel data on the morphological diversity of sedges (Carex: Cyperaceae). Our goals were to generate novel, specimen-based morphometric data that we and the students could use to investigate plant diversification and to mentor students in all aspects of science: hypothesis generation, data gathering, data analysis, and communicating findings and inferences. More importantly, we aimed to inspire in students an appreciation for and enjoyment of the process of science. Protocols and classroom activities were developed in collaboration with five teachers who interned in our lab. Teachers participated in authentic sedge research in our lab, then developed and modified classroom protocols for their students. Over the course of three years, 330 students from two schools made morphological measurements on 276 unique Carex specimens and replicated measurements on 96 of these. Student data were validated by comparison to data generated by in-lab trained observers. Students achieved 81% high-quality (retainable) data in our second year of the project, reflecting improvements in our approach to training and mentoring. In anonymous postparticipation surveying, students demonstrated that they had generated new insights or knowledge by participating in this project. We consider the hands on approach that we took in this project to be a fruitful means of developing local collaborations that increase students' and teachers' understanding of the research process and plant biodiversity.

Two species-rich lineages of Carex, C. sect. Phacocystis and the Vesicariae alliance, show a replicated and parallel radiation in the Northern hemisphere. Each group possesses a clade consisting of mostly boreal to arctic species and a second clade comprising more southerly distributed species. In this study, we ask if molecular differentiation is paralleled in both radiations by the diversification of quantitative morphological characters. We use nucleotide diversity to assess the molecular differentiation and methods derived from symbolic data analysis (SDA) for addressing the morphological diversification. The SDA turned out to be valuable for biological meta-analysis, because it is able to deal with the whole information content of interval and range data, respectively. We observed for some characters a weak correlation between molecular and morphological differentiation that, however, disappeared after Bonferroni correction. Therefore, in these phylogenetically young and radiating groups, diversification of molecular markers and quantitative morphological characters seem to be decoupled or hidden by homoplasy and plasticity.

The concept of limiting similarity predicts that closely related taxa are less likely to co-occur than expected by chance. The degree to which the phylogenetic relatedness in plant communities is in accord with limiting similarity has been little tested at the scale where the consequences of adaptive differentiation during speciation should be most evident: the scale of neighboring, congeneric plants within a community. To quantify species co-occurrence patterns in relation to environment, we sampled sedge species, their rooting level relative to the water table, and the water pH in 2,124 0.25 m² quadrats distributed across 29 subarctic fens in the central Labrador Peninsula. We estimated phylogenetic relationships using four DNA regions (ETS, ITS, matK, trnL-trnF) for all species of Carex (42), Eriophorum (6), and Trichophorum (2) in the region, of which 21, four, and two, respectively, occurred in the sampled fens. We demonstrate that closely related species of Carex are less likely to co-occur than expected by chance using 1) a probabilistic method to test the significance of pairwise co-occurrence patterns of species, and 2) linear mixed modeling to relate these patterns to phylogenetic relationships and ecological tolerances along gradients of substrate pH and rooting level in relation to the water table. The results also indicate that suites of species with significant mutual pairwise co-occurrence belong to distant lineages within the Cariceae-Dulichieae-Scirpeae clade of Cyperaceae and have stabilizing niche differences. We suggest that niche differentiation during the evolution and diversification of a clade of wetland Carex species over the past few million years, especially during the dynamic glacial cycles of the Pleistocene, has resulted in diverse sedge communities that share space and resources in harsh northern peatland habitats.

In eukaryotes, we can recognize two kinds of chromosomes, based on the location of the kinetochores. The majority of eukaryotes have monocentric chromosomes, in which kinetochoric activity is concentrated in a single locus. In several unrelated eukaryotic lineages, chromosomes are holocentric, having diffuse centromeric / kinetochoric activity along the length of the chromosome. Whether holocentric chromosomes are derived or ancestral is still under debate. This study uses the phylogenetic tree from Time Tree of Life project, comprising more than 50,000 sampled species, to reconstruct the evolution of holocentry. Asymmetrical two-state Markov (Mk2) models were compared with BiSSE models to assess sensitivity of our conclusions to possible effects of holocentry on lineage diversification rates. Our analyses based on Mk2 and BiSSE models inferred that the rate of transition from holocentric to monocentric chromosomes is two orders of magnitude higher than the reverse direction. The ancestral state of all eukaryotes is ambiguous depending on the model, inferred to be either monocentric (Mk2) or holocentric (BiSSE). Whatever the direction, the multiple transitions and high diversity of centromere organization across the tree of life are what we would expect if there are selective advantages to both chromosome types. Understanding those selective advantages is key to understanding how genetic information is organized and transmitted from one generation to the next, and why these major evolutionary transitions in centromere organization have occurred in the first place.

Monachosorum arakii Tagawa is a plant species endemic to the western part of the main island of Japan. It is characterized by large bulbils on the rachises and is a close relative of M. henryi Christ, which can be found in the Sino-Himalayan region and is not present in Japan. Although M. arakii was reported to be a hexaploid, we determined that it is a pentaploid based on chromosome counts. All of the herbarium specimens examined, including the holotype, had irregularly shaped spores, suggesting that this is a sterile hybrid species. Analysis of the nuclear gapCp sequences also supported its hybrid origin from M. henryi (tetraploid) and M. nipponicum Makino (hexaploid). It should be noted that the parental species of M. arakii, which are endemic to Japan, only co-occur in China. It is possible that the hybrids are relicts from the time when M. henryi were also present in Japan, and are now reproducing only vegetatively by rhizome division and bulbil production. The updated taxonomic treatments for Monachosorum species provided in the current study recognize four species and two hybrid taxa.

Dryopteris subgenus Nothoperanema (Dryopteridaceae) includes sections Acrophorus, Diacalpe, Nothoperanema, and Peranema. Phylogenetic relationships among these sections and their relationship to sect. Dryopsis (genus Dryopteris subgenus Erythrovariae, Dryopteridaceae) are unclear. Additionally, previous phylogenetic work has not included Stenolepia, which has been suggested as an important relative of Peranema based on morphology. In this study, we examined phylogenetic relationships within subgenus Nothoperanema by including Stenolepia and utilizing six plastid regions (∼5,500 characters). Our inferred phylogeny revealed that sect. Dryopsis is not monophyletic. The Nothoperanema clade is highly supported, and includes sect. Acrophorus, sect. Diacalpe, sect. Nothoperanema, sect. Peranema, certain Dryopsis species, and Stenolepia. By re-examining diagnostic morphological characters, we establish and describe two new sections under subgenus Nothoperanema: sect. Shiehia and sect. Stenolepia. This revision accommodates new species transferred from sects. Dryopsis and Stenolepia, and makes subgenus Nothoperanema and each of its sections natural groups. Finally, we provide a table with morphological comparisons and a key to sections.

The previous infrageneric classification of Mucuna (Leguminosae, Papilionoideae) recognized two subgenera, M. subg. Mucuna and M. subg. Stizolobium, but that classification is not supported fully by molecular phylogenetic analyses, which reveal three main clades in Mucuna (rather than the traditional two). A new taxon M. subg. Macrocarpa is proposed based on the results of a molecular phylogenetic analysis, supported by fruit characters and biogeography. Historically, the representatives of this new subgenus were considered as members of M. subg. Mucuna, but species of subgenus Macrocarpa differ from species of the other two subgenera by their longer ovaries containing a higher number of ovules and, consequently, longer pods containing more seeds, and by the different fruit length to width ratio. This study presents a new infrageneric classification of the genus Mucuna. The six species of M. subg. Macrocarpa are reviewed, and species descriptions, typifications (including five new lectotypes), a distribution map, and a species identification key are presented.

The genus Fagus (beech, Fagaceae) consists of about 10 species discontinuously distributed in East Asia, eastern North America, and Europe. Fagus multinervis occurs only on Ulleungdo Island, Korea, and is an important component of the island's plant community. The species was described primarily based on one of its stem characteristics: it branches at the base, producing several primary trunks. In part because no extant Fagus species are found in mainland Korea, and because the closest populations of Fagus are found in Japan, F. multinervis has been considered to be derived from the Japanese species, F. japonica. However, a recent study synonymized F. multinervis under F. engleriana and proposed that the beech population of Ulleungdo Island was derived instead from China via long-distance dispersal. Fagus multinervis is morphologically very similar to F. engleriana, but it can be distinguished by having rhombic lenticels that are vertically elongated. We determined the nucleotide sequences of the trnK-matK, trnL-trnF, trnH-psbA, and atpB-rbcL regions of plastid DNA and the second intron of the nuclear LEAFY gene from accessions of eight species, including eight F. multinervis individuals, in order to clarify the phylogenetic placement of this insular species. Phylogenetic analyses show that F. multinervis is monophyletic, and that it is closely related to F. engleriana and F. japonica. However, a sister relationship of F. multinervis with either of those species is not resolved. Therefore, our molecular data support the distinctness of F. multinervis as an endemic on Ulleungdo Island. Furthermore, incongruence between plastid and nuclear data suggests that F. multinervis may have originated via hybridization.

Climatic oscillations during the last glacial maximum (LGM) have played important roles in the distributions and genetic structures of extant species. Here, we investigated the population structure of a deciduous shrub species, Rhododendron dauricum L., across its current geographic distribution in northeastern China based on six chloroplast regions (trnS-trnfM, trnL-ndhJ, rpoC1-rpoB, trnS-trnG, trnH-psbA, and trnK-matK). A total of 11 haplotypes were identified. The results showed a significant geographic distribution pattern (N_ST > G_ST p < 0.01) in northeastern China. In addition, our results showed that there were high levels of genetic diversity in R. dauricum and that more than 70% of the genetic variability was distributed among groups. Furthermore, results from the neutrality test failed to identify population expansion at the whole-species level. These findings together suggested that R. dauricum shows spatial genetic structure and that the LGM has had profound impacts on the geographic distribution and genetic variability of this species.

We provide a systematic update of Pradosia (Sapotaceae, Chrysophylloideae), including overall morphology, a key to all species, comprehensive morphological descriptions, geographic distributions, and important characteristics for each species. Phylogenetic analyses based on molecular data demonstrated that the genus is monophyletic and includes three main clades. Twenty-three species of Pradosia are accepted, which are mostly distributed in lowland rainforests on either white-sand or clayish soils in tropical South America. A rotate corolla with a short tube, lack of staminodes, a drupaceous fruit with plano-convex cotyledons, an exserted radicle below the cotyledons, and the absence of endosperm are diagnostic for the genus. Two names are reduced into synonymy, viz. Pradosia atroviolacea Ducke, syn. of P. grisebachii (Pierre) T. D. Penn., and Pradosia verrucosa Ducke, syn. of P. glaziovii (Pierre) T. D. Penn. The affinity of P. argentea (Kunth) T. D. Penn., a species known only from the type collection, remains uncertain and for now excluded from the genus.

Sphaerorrhiza, a genus of herbaceous plants endemic to the Cerrado domain in Brazil, was recently segregated from the genus Gloxinia and placed in its own monotypic subtribe Sphaerorrhizinae. Most information on this little-known taxon derived from the observation of a single species and a limited number of collections. Using new material representative of all recognized species we reassess the monophyly of Sphaerorrhiza and its phylogenetic placement within Gesnerioideae based on the analysis of nuclear (ITS) and plastid (atpB-rbcL, matK, rpl16, rps16, trnL-trnF) DNA sequences. Our results support the monophyly of the genus and its segregated position from the other clades of Gesneriaceae. A taxonomic revision of Sphaerorrhiza is presented, including new anatomical and morphological data and the first reported chromosome number for the genus. Four species are recognized and two species are described as new, S. rosulata and S. serrata. Descriptions, illustrations, and a distribution map, as well as a key to the species of Sphaerorrhiza, are provided.

Elatine rotundifolia was described in 2008 from Ecuador as a new species because of its unique morphology and geographical distribution. However, an examination of type material for E. rotundifolia suggested to us initially that this taxon had been assigned incorrectly to Elatine, despite some superficial similarity to that genus. This possibility was investigated using morphological and molecular data. We found that E. rotundifolia differed from other members of Elatine by several vegetative and reproductive features, which indicated a distant alliance closer to Linderniaceae (Lamiids; Asterids) rather than Elatinaceae (Fabids; Superrosids). We then conducted a phylogenetic analysis of DNA sequences from the internal transcribed spacer region, which included isotype material of E. rotundifolia, as well as various representatives of Elatinaceae, Linderniaceae, and other angiosperm clades. The molecular data resolved E. rotundifolia among several accessions of Micranthemum (Linderniaceae) in a position quite remote phylogenetically from accessions of Bergia and Elatine (Elatinaceae). From these results, we conclude that the name E. rotundifolia refers to a taxon that was misplaced in Elatine, and represents instead a member of Micranthemum (Linderniaceae), and possibly is synonymous with the aquatic species M. umbrosum.

We propose a new classification for the South American species of the genus Bartsia L. and relatives recently included in an expanded treatment of the genus Bellardia (L.) All. This new classification reflects their evolutionary history, and is based on morphological and molecular evidence, biogeographic hypotheses, and rates of diversification for these species. Additionally, we rearranged the current taxonomic classification of close relatives so that the current circumscriptions encompass only monophyletic groups. Some of these changes include the creation of a new genus, Neobartsia Uribe-Convers and Tank (47 spp.), as well as the reclassification of Bellardia latifolia (L.) Cuatrec. back to Parentucellia latifolia (L.) Caruel. These taxonomic changes are important for proper communication within the large Rhinantheae clade of Orobanchaceae, and for the interpretation of biogeographic patterns and diversification processes of these species.

Fruit and trichome structures of Apiaceae subfamily Mackinlayoideae were studied in detail using light microscopy to identify morphological features that might be useful in delimiting this subfamily and to identify structural characters that can be used to define subclades identified by molecular phylogenetic studies (e.g. the Centella and Xanthosia clades). Three types of trichomes are present in all genera except Mackinlaya and Schoenolaena: equisetiform (Actinotus, Centella, and Chlaenosciadium), digitiform (Apiopetalum, Micropleura, and Pentapeltis), and dendritic (Xanthosia). Fruits usually have laterally compressed mericarps. Dorsal bundles and rib ducts are usually branching (or branching and anastomosing) in most taxa studied. Branching and anastomosing vittae only occur in Apiopetalum, which is also characterized by sclereids in the mesocarp. Two types of crystals were found, rhomboidal and druse. Carpophores are entirely absent from the subfamily, but homologous features are present in the form of ventral bundles. Within Mackinlayoideae, the Actinotus-Apiopetalum and Mackinlaya clades can be distinguished from the Centella clade (Centella, Micropleura, Pentapeltis, and Schoenolaena) and Xanthosia clade (Xanthosia and Chlaenosciadium) in having fleshy fruits, specialized trichomes, and sclereids in the fruit mesocarp. Despite its phylogenetic position, Mackinlayoideae are more similar to Araliaceae than to Azorelloideae or the rest of Apiaceae, suggesting the retention of plesiomorphic character states, such as digitiform trichomes, laterally compressed mericarps, and sclereids. The equisetiform and dendritic trichomes are synapomorphies of Centella and Xanthosia clades and the Xanthosia clade differs from the Centella clade in lacking digitiform trichomes. Overall, trichome and fruit characters provide useful structural features in defining Mackinlayoideae and in differentiating its subclades.

This study has the purpose of reviewing the species of Campylocentrum with terete leaves. While 15 names have been proposed in the group, here we recognize only six previously described species. We also describe a seventh, new species, C. labiakii, which is endemic to the Brazilian state of Espírito Santo. Finally, this study also provides typifications, complete synonymies, conservation statuses, complete descriptions, distribution maps, and an identification key to the species in question.

We describe and illustrate Mastigostyla coronata, a new species of Iridaceae from the high Andes of Jujuy (Argentina), morphologically similar to Mastigostyla vargasii. The inclusion of this new species in Mastigostyla is supported by a phylogenetic analysis based on plastid markers. We also present a morphological comparison among the sub-acaulescent species of Mastigostyla (including Cardenanthus), and a key to those species.

The floristic inventory of the Sierra de Quila Natural Reserve, in western Mexico, resulted in the discovery of Polianthes quilae (Polianthes subgen. Bravoa). The novelty is related to P. cernua and P. geminiflora var. clivicola but is distinguished by the erect lanceolate leaves, glauous inflorescence with 4–21 floral nodes, 0.9–2.1 cm long pedicels, tubular-ventricose and bicolorous perigone with ascending lobes, and filament insertion site 3–5 mm above ovary apex. Data on geographic distribution and ecology, phenology, and conservation status are presented. Lastly, a key to all species of Polianthes is provided.

El inventario florístico del Área de Protección de la Flora y la Fauna Sierra de Quila, en el occidente de México, resultó en el descubrimiento de Polianthes quilae (Polianthes subgénero Bravoa). El nuevo taxón se relaciona con P. cernua y P. geminiflora var. clivicola pero se distingue por sus hojas erectas y lanceoladas, inflorescencias glaucas con 4–21 nudos florales, pedicelos de 0.9–2.1 cm de longitud, perigonio tubular-ventricoso y bicolor con los lóbulos ascendentes y por la inserción de los filamentos 3–5 mm por arriba del ápice del ovario. Se aportan datos sobre la distribución geográfica, hábitat, fenología y estado de conservación del taxón nuevo. También, se provee una clave para la identificación de las especies de Polianthes.

Taxonomic delimitation within the Andean Festuca setifolia complex s. l. has been fraught with difficulty due to the large range of morphoanatomical and epidermal variation among species coupled with varying opinions on what diagnostic characters should be used to distinguish species. We shed light on this through using multivariate analysis (PCA, PCoA and cluster analysis), based on 20 variables (morphoanatomical and epidermal characteristics), to elucidate patterns of variation within this group and to test the validity of current species delimitations. The analysis of 89 OTU's recognized six clearly separated groups, corresponding to F. fiebrigii, F. hieronymi, F. lilloi, F. linigluma (a new species described here), F. samensis, and F. setifolia. The OTU's corresponding to F. fiebrigii were grouped as outliers with respect to the F. setifolia complex s. l. and were excluded from multivariate analysis. We redefine the F. setifolia complex s. s. to include F. linigluma, F. lilloi, and F. setifolia, which possess unique characters differentiating them from other members of the complex s. l. The status of type material was clarified, with F. tucumanica synonimised under F. lilloi, while F. erecta var. mutica, F. erecta var. aristulata, and F. dissitiflora var. loricata, F. weberbaueri, F. dissitiflora var. villipalea, and F. hieronymi subvar. expansa were placed as synonyms of F. fiebrigii, with the taxonomic concept of F. fiebrigii being redefined. We present an identification key, descriptions, illustrations, and revised geographic ranges for F. fiebrigii and the species of the F. setifolia complex s. l., including the new species, Festuca linigluma, from the central Andes.

A taxonomic treatment of Tapura from the Brazilian Atlantic Forest is presented. Tapura follii is endemic to Espírito Santo State and the distribution of T. wurdackiana is expanded to northeastern Brazil. Two new species, T. martiniae and T. zei-limae are described and micromorphological characters of leaf trichomes and pollen grains, analyzed by SEM, are discussed for the group. In addition, the species are compared to T. amazonica, the most widespread species of Tapura. Descriptions, illustrations, distribution maps, and an identification key for the Atlantic Forest species of Tapura are also provided.

Tovomita comprises approximately 50 species that are mainly distributed in moist forests of the Neotropics. In Brazil there are 34 species, which occur in the Amazon region and along the Atlantic coast. We here describe and illustrate the Tovomita species from the Brazilian Atlantic Forest, as well as characterize the leaf morphology of these taxa. Leaves were cleared and their venation was analyzed to look for diagnostic characters related to architecture and the relationship between the secondary and intersecondary veins. Eleven species of Tovomita were recorded, which have distributions ranging from the state of Rio Grande do Norte to the state of Rio de Janeiro. An identification key, based on the analysis, and distribution maps are provided. Tovomita salimenae, a new and vulnerable species endemic to the state of Minas Gerais, is described and two synonyms and nine lectotypifications are proposed. This work also revealed that seven species have larger distributions than previously thought and two species are critically endangered (T. iaspidis and T. megantha). The most relevant characters used to identify the studied species were exudate color, venation pattern, and bud shape.

Serjania rzedowskiana (Sapindaceae-Paullinieae), a new species from the Zicuirán-Infiernillo Biosphere Reserve of Michoacán, Mexico, is described and illustrated. The novelty differs from its congeners by having fruits with 3 indehiscent, wingless cocci, and by its sub-transversely obovoid seeds that occupy less than half of the locule. In addition, micromorphological features of the leaves, flowers and pollen grains are investigated. The distinctive fruit morphology of this new species is discussed in relation to other species of Serjania. In addition, a key is provided to differentiate the new species from other Mexican Serjania with similar vegetative characters (i.e. trifoliolate leaves and flowering branchlets with three peripheral vascular cylinders).

A new species of milkweed vine from Texas, Matelea hirtelliflora (Apocynaceae), is described and illustrated. This species is similar to congeners in the southeastern United States, but is distinguished by hirtellous corollas with shorter petals than its presumed closest relatives and by corona lobes with fleshy segments, each with two triangular projections. The species is illustrated and compared to similar species of eastern Texas and the eastern United States. A key is provided for the species of Matelea in eastern Texas and extreme southeastern Oklahoma, and a distribution map is provided for the new species.

Analysis of ITS sequence data was used to help to elucidate species relationships in the Eupatorium mohrii complex, which includes sexual diploid and apomictic polyploids. Lack of variation and polymorphism in ITS sequences showed that E. recurvans and E. mohrii comprise diploid and autoploid populations, respectively, and should be recognized as a single species, for which the latter name has priority. Populations that collectively have been called E. anomalum, which has previously been shown to be apomictic and suggested to be of allopolyploid origin, were discovered to include two different genetic combinations that are geographically separated. The more southerly populations, including those at the type locality, were suggested by ITS sequence data to be hybrid derivatives of E. mohrii and E. rotundifolium. Northern populations from Virginia and North Carolina appeared to be hybrid derivatives of E. mohrii and E. serotinum, confirmed by data from highthroughput sequencing of the nuclear ribosomal repeat region. Because these northern populations have characteristic phenotypic features and are localized to a distinct habitat in interdune swales, they are described here as Eupatorium maritimum. A chromosome count of 2n = 30 was obtained from a sample of E. maritimum, suggesting that it is a triploid. Based on its uncommon occurrence in a habitat that is geographically restricted, E. maritimum appears to be a rare species that is in need of protection.

Famatinanthus, a recently established monotypic genus, has a unique style type with a cobblestone-like surface. These cobblestonelike units comprise several epidermal cells that often have periclinal walls, resulting in a partially “double epidermis.” The particular epidermis supports the exclusion from the genus Aphyllocladus (based on morphological data) as well as the elevation of the genus Famatinanthus to tribe and subfamily rank (based on chloroplast DNA data). To demonstrate the uniqueness of the stylar morphology of Famatinanthus, its styles and those of the remaining four species of Aphyllocladus were studied by SEM and histological sections. In addition, representatives of the basal tribes that share non-stylar characters with Famatinanthus, namely Gochnatieae, Hyalideae, Onoserideae, and Stifftieae, were studied in comparison. Due to the lack of stylar hairs, Famatinanthus is clearly distinct from Aphyllocladus, Onoseris (Onoserideae), and Hyaloseris (Stifftieae), which have stylar hairs on the entire dorsal side or only on the upper part of the stylar branches. Famatinanthus shares the glabrous stylar surface with Gochnatieae and Hyalideae, but in the latter tribes the rounded stylar branches are dorsally thickened (Gochnatia style type). A partially “double epidermis” can episodically be observed in the genus Stifftia, which has not been previously mentioned as a relative of Famatinanthus. The extensive sclerenchymatic tissue present in the stylar branches of Famatinanthus, however, is not found in Stifftia.

The genus Laretia Gillies & Hook. comprises a single species, L. acaulis (Cav.) Gillies & Hook., of xerophilous subshrubs that form flat compact cushions. It is endemic to southern South America and is distributed through the high Andes of San Juan and Mendoza provinces in Argentina, and Atacama to Maule regions in Chile. Descriptions of Laretia are available only from the protologue and from a few regional floras; these are not comprehensive and are based on few specimens. Moreover, the actual geographic distribution of the genus has been questioned. In this work we present a taxonomic treatment for Laretia that includes field work, analysis of the protologue, and an exhaustive revision of herbarium material. We also analyze and describe the morphology and anatomy of its fruits because of their diagnostic importance in the family. We provide a detailed morphological description, ecological and ethnobotanical information, and illustrations of the genus. Additionally, we present a map that shows the geographical distribution of Laretia, designate lectotypes for three names, and finally analyze and resolve nomenclatural problems regarding two names (Laretia compacta and Laretia yareta) that have not been included in recent treatments and require revision in order to understand the limits of the genus.