New molecular and ecological data have necessitated taxonomic revisions of several species complexes within Polemonium (Polemoniaceae), including P. foliosissimum, an herbaceous perennial widespread in the Intermountain West of the United States. As currently circumscribed, P. foliosissimum is a highly polymorphic species of four taxonomic varieties. One of the most striking morphological traits of the species is its diversity in flower color, which is unusual for the genus. Several species have been proposed based on this variation in flower color. However, these names have been treated as infraspecific taxa because previous authors have concluded that the presence of micropollen grains throughout the geographic range of the species complex indicated partial hybrid sterility and therefore incomplete barriers to gene flow. However, recent evidence suggests that micropollen is instead due to a gynodioecious breeding system. Using 128 nuclear loci and eight quantitative morphological traits, I clarify relationships and taxonomy within the species complex. I show that what is currently circumscribed as four varieties of P. foliosissimum represent five species that, in addition to differing in corolla color, differ in leaflet number, corolla size, and vegetative and floral pubescence. I propose a new species endemic to the White Mountains of southeastern Arizona, Polemonium apachianum. This study provides a new phylogenetic context and taxonomic circumscription to serve as a framework for future research on the evolution of floral color and sexual systems in a previously misunderstood but evolutionarily exciting system.

We sampled 130 individuals (2 to 25 per taxon) of Pinus subsections Ponderosae and Sabinianae. Nucleotide sequences were obtained by targeting 703 low copy nuclear genes. From the unenriched portion of the short reads, we assembled nearly complete plastome nucleotide sequences. We used 600 nuclear genes and the plastome sequences to create phylogenies and species trees that we compared to evaluate cytonuclear concordance and reticulation. We found that Pinus jeffreyi belongs with Pinus subsect. Sabinianae based on morphological synapomorphies as well as strong molecular phylogenetic support. Pinus ponderosa sensu lato is paraphyletic, and we suggest treatment as three species: P. ponderosa sensu stricto (with P. ponderosa var. ponderosa, P. ponderosa var. benthamiana, and P. ponderosa var. washoensis), P. scopulorum, and P. brachyptera. The persistence of lineages with the footprints of ancient nuclear introgression (labeled bpw in clade N4) and chloroplast capture (labeled bpw in clade P1) should caution species identification in Pinus subsection Ponderosae based on limited molecular data. The hybrid frequency was low based on cytonuclear discordance, and the persistence of an ancient P1 plastid clade is a better explanation than hybridization between P. ponderosa and P. jeffreyi for unexpected plastid associations in the western Sierra Nevada, USA. We identified a new potential zone of ancient admixture between P. ponderosa and P. scopulorum in Idaho, USA. Some populations of P. arizonica, P. brachyptera, P. engelmannii, and P. scopulorum in the USA are more closely related to taxa with distributions limited to Mexico than they are to each other. To integrate phylogeny and taxonomy, future work should sample widely in Mexico and the USA, score morphological characters (including seedling characters from the known seed parent), on the same individual as used for molecular data, and use methods that are based on individuals rather than population frequencies.

Glossopetalon inhabits arid regions in the American west and northern Mexico on limestone substrates. The genus comprises four species: G. clokeyi, G. pungens, G. texense, and G. spinescens. Three of the species are narrow endemics. The fourth, G. spinescens, is a widespread species with six recognized varieties. All six varieties are intricately branched shrubs that have been difficult to identify due to a lack of clearly delineating morphological characters. Characters typically used to differentiate the varieties of G. spinescens, such as stem coloration, leaf blade size, and presence of stipules, are highly variable within and among populations. A custom protocol of double digest restriction-site associated DNA sequencing (ddRAD) was used to resolve the phylogeny of Glossopetalon and address if population genetic data analyses (such as STRUCTURE, SVDquartets, and phylogenetic networks) support the recognition of six varieties of G. spinescens. Glossopetalon was fully supported as monophyletic and G. pungens was resolved sister to the remaining taxa in the genus. The varieties of G. spinescens were resolved as two distinct lineages corresponding to their biogeography, one to the northwest (lineage 1) and one to southeast (lineage 2) of the species range. Glossopetalon clokeyi was resolved at the base of lineage 1 and G. texense was embedded within lineage 2 sister to G. spinescens var. spinescens. Taxonomic changes include the recognition of G. texense and G. clokeyi as varieties of G. spinescens and description of a unique population from northern Arizona as a new variety, G. spinescens var. goodwinii.

The history of the study on pterido-flora in Vietnam is reviewed. Two new records, Adiantum capillus-junonis and Actinostachys wagneri are reported for Vietnam based on our new collections. A new species, Hymenophyllum bryoides, is described to accommodate its morphological and genetic distinctiveness from other congeneric species. Photographs of key characters, distributions, ecology, and notes on all the above species are provided.

This study summarizes the taxonomy of the species of Maranta from northeastern Brazil. While 20 names have been proposed in the region, only 13 are accepted. We provide two new records, M. rugosa and M. polystachya, and five new species are described, of which M. bahiensis and M. villosovaginata are endemic to Bahia, M. chrysogina to Ceará, M. vieirae to Maranhão, and M. lorifolia occurs in Bahia and Espírito Santo. Maranta noctiflora, M. parvifolia, M. phrynioides, and M. rupicola L. have distributions outside of the study area, while M. anderssoniana and M. hatschbachiana are synonymized. Our final checklist includes 21 species, which represent more than half of the species in the genus, highlighting northeastern Brazil as a center of diversity for Maranta. Among the species listed, M. lorifolia, M. tuberculata, and M. zingiberina are thought to be endangered (EN), while M. gigantea is likely critically endangered (CR). Finally, this study provides informal conservation statuses, descriptions, distribution maps, and an identification key to the species. Typifications for M. subterranea and M. polystachya are also provided.

Physarieae is a small tribe of herbaceous annual and woody perennial mustards that are mostly endemic to North America, with its members including a large amount of variation in floral, fruit, and chromosomal variation. Building on a previous study of Physarieae based on morphology and ndhF plastid DNA, we reconstructed the evolutionary history of the tribe using new sequence data from two nuclear markers, and compared the new topologies against previously published cpDNA-based phylogenetic hypotheses. The novel analyses included ca. 420 new sequences of ITS and LUMINIDEPENDENS (LD) markers for 39 and 47 species, respectively, with sampling accounting for all seven genera of Physarieae, including nomenclatural type species, and 11 outgroup taxa. Maximum parsimony, maximum likelihood, and Bayesian analyses showed that these additional markers were largely consistent with the previous ndhF data that supported the monophyly of Physarieae and resolved two major clades within the tribe, i.e., DDNLS (Dithyrea, Dimorphocarpa, Nerisyrenia, Lyrocarpa, and Synthlipsis) and PP (Paysonia and Physaria). New analyses also increased internal resolution for some closely related species and lineages within both clades. The monophyly of Dithyrea and the sister relationship of Paysonia to Physaria was consistent in all trees, with the sister relationship of Nerisyrenia to Lyrocarpa supported by ndhF and ITS, and the positions of Dimorphocarpa and Synthlipsis shifted within the DDNLS Clade depending on the employed data set. Finally, using the strong, new phylogenetic framework of combined cpDNA + nDNA data, we discussed standing hypotheses of trichome evolution in the tribe suggested by ndhF.

It is generally believed that cliffs bear low biodiversity because of their harsh habitats. However, another reason, i.e. insufficient investigation caused by the inaccessibility of the cliffs, could not be excluded. In the genus Aster, two cliff species, Aster fanjingshanicus and Aster tianmenshanensis, respectively growing on slate and limestone cliffs, were previously described. During our extensive field investigations, a third cliff species of Aster growing on granite cliffs from eastern China was found. Based on evidence from molecular phylogeny, morphology and micro-morphology, we propose that it should be treated as a new species and named Aster sanqingensis. It is described and illustrated here. Considering its limited number of individuals, highly localized distribution, and disturbed habitat, we propose to treat it as a Critically Endangered species. Our new finding indicates there is cryptic biodiversity on the cliffs remaining to be discovered.

Strychnos is a pantropical genus of Loganiaceae (Gentianales), with approximately 200 species, that lacks a detailed worldwide phylogenetic understanding until now. We investigated the global phylogeny of the majority of Strychnos species, and evaluated morphological and key character patterns to discuss congruence between phylogenetic clades and sectional classification systems. We included 147 ITS sequences across 12 genera, with 127 samples (103 species) of Strychnos and 20 outgroup accessions (19 species) in a Bayesian analysis. Tribes Antonieae, Loganieae, and Spigelieae were supported as monophyletic, but Strychneae was resolved as polyphyletic due to the positioning of Gardneria placed outside of the Strychnos + Neuburgia clade. Strychnos was supported as strongly monophyletic with 12 strongly supported clades, but the relationships among many of these clades were not well resolved. Most of the 12 sections in the current infrageneric classification system of Strychnos were resolved as non-monophyletic, indicating the need for a revision of the sectional divisions. Characters common in species placed within the relatively more nested clades include a non-climbing habit, invasion of non-rainforest habitats, absence of tendrils, absence of secondary phloem, and elongated corolla tubes, suggesting that these characters are relatively derived conditions in the genus. Inflorescence position, fruit size, and fruit wall thickness are extremely variable and were distributed among various clades in our phylogeny. Stamen, pistil, seed and seed coat, and phytochemical characters have figured prominently in the taxonomy of the genus, but are as yet incompletely described, thus preventing significant inference about their evolution. Most of the 12 well-supported clades within Strychnos are restricted to specific continents, sometimes with limited dispersion between neighboring continents, suggesting a history of repeated cross-oceanic dispersal or vicariance patterns. The Neotropical clades nested within the African clades have the shortest branches and the most unresolved topologies, probably indicating relatively recent radiation in the Neotropics.

Leucostegia has been long recognized as a small fern genus with only two species, L. immersa and L. pallida. Here we elevate a variety of L. immersa to species level and make the new combination Leucostegia amplissima based on morphological and molecular phylogenetic evidence. Morphologically, Leucostegia amplissima differs from L. immersa by having larger evergreen fronds, smaller indusia, and glandular hairs on the basal stipes. The study of Taiwanese populations further suggested an ecological divergence between L. immersa and L. amplissima.

Lineage recombination is an important source of genetic and morphological variation in species-rich groups of plants. Tetraploids that are intermediate in morphology and ecology with respect to sympatric diploids are regularly hypothesized to be the products of hybridization. Arctostaphylos mewukka is one such intermediate tetraploid long regarded as the result of hybridization and genome duplication among divergent and geographically overlapping diploids widely distributed across the western slope of the Sierra Nevada. Here we set out to test this hypothesis leveraging the notion that allopolyploids arise repetitively and may show signs of reciprocal organellar exchange among species between maternal and paternal progenitors. We compared nuclear ribosomal and plastid sequence data acquired from samples within and outside this target species complex. Molecular sequence data show striking patterns indicative of widespread reticulation and chloroplast capture events across the genus Arctostaphylos. Results support the notion that outcrossing, long-lived woody plant species such as members of the genus Arctostaphylos can retain a secured morphological identity despite ongoing influence of interspecific gene flow that would otherwise render species boundaries vulnerable to dissolution.

Eucnide (Loasaceae) consists of about 15 species distributed across Mexico, Guatemala, and the North American Southwest, a geographically complex landscape made up of floristically unique deserts, large mountain ranges, and a large, geographically isolated peninsula. This complex geography is credited for high levels of biodiversity and endemism in the region and we examine relationships between geography and cladogenesis in Eucnide. In the most recent treatment of the genus, Thompson and Ernst recognize three sections of Eucnide differentiated based on floral morphology. To date, no molecular phylogenetic studies have broadly sampled species in this genus. We used Bayesian and maximum-likelihood phylogenetic analyses of one plastid marker (matK) and one nuclear marker (ITS) to: 1) test the monophyly of Eucnide sections and assess whether the existing taxonomy sufficiently circumscribes diversity within the genus; 2) assess the divergence times of Eucnide lineages to determine when the major clades diversified; and 3) estimate the ancestral range of Eucnide and hypothesize patterns of geographical diversification of the genus. We found that not all infrageneric units of Eucnide are monophyletic and the taxonomy needs revision. Additionally, the major clades of Eucnide are predominantly restricted to geographic regions, suggesting that species have frequently diversified within geographic areas. The ancestral range of Eucnide was inferred to be widespread, and the divergence times of the major clades coincide with major geological events, particularly, the formation of the North American warm deserts, the isolation of the Baja Peninsula, and the uplift of the Trans Mexican Volcanic Belt. This suggests that major geological/climatic events may have contributed to the diversification of the genus.

Cereinae comprises 14 genera distributed in Neotropical dry forest formations such as in the Caatingas of northeastern Brazil or in rocky outcrops in the north of southeastern Brazil. Historically, the taxonomy of the group has been very controversial, especially regarding generic circumscriptions, and phylogenetic relationships within the group are still poorly understood. To investigate the delimitation of the subtribe and infra-subtribal relationships, we performed a phylogenetic analysis including 50 taxa representing 13 genera using one nuclear (PhyC) and four cpDNA (petL-psbE, trnL-trnT, trnS-trnG, and rpl16) regions. Our results show a monophyletic Cereinae with high support in Bayesian, maximum parsimony, and maximum likelihood analyses based on combined matrices. Although our results expand the knowledge of generic relationships, we emphasize the need for further molecular phylogenetic studies combined with ecological evidence to clarify relationships at the more inclusive nodes of the subtribe.

In this study, five species of Cathedra (Olacaceae s. l.) were recognized, four of them endemic to Brazil and one widely distributed, occurring in Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela. Cathedra rupestris, a new species described here, is endemic to campos rupestres (Cerrado) in the state of Bahia, and is differentiated from other species of the genus mainly by reticulate bark, length of pedicel in flower (1.5–2.2 mm), length of petals (3–3.5 mm), as well as by the proportion of the hypogynous disk in relation to the fruit, which in this species is limited to the base of the drupe. Regarding informal conservation status, C. bahiensis, C. grandiflora, and C. rubricaulis are suggested as Endangered, while C. acuminata and C. rupestris as Least Concern and Critically Endangered, respectively. Here the genus is reviewed, nomenclatural (one synonymization and two typifications) and geographic distributional updates are provided, in addition to an identification key, descriptions, and illustrations. Emended descriptions are also provided for two species.

A RAD-seq phylogeny is presented for the genus Ulmus, and a revised infrageneric classification is given, with keys, descriptions, and range maps for the subgenera and sections. The previously accepted classification was based on a cpDNA phylogeny, but several well-marked clades in the chloroplast phylogeny are not recovered in the RAD-seq phylogeny and do not seem to represent valid clades in the organismal phylogeny. Ordination and STRUCTURE analysis support a broad species concept in Ulmus sect. Foliaceae and demonstrate interspecific hybridization in the section. Several sections of the genus are disjunct between Asia, Europe, and North America, indicating dispersals between the northern continents with inferred dates from ca. 20 Ma to ca. 3 Ma. Morphological variation is discussed, and some characters previously considered characteristic of Ulmus subg. Oreoptelea (narrowly winged achenes, ciliate achene margin) are shared with the unrelated U. villosa. A new subgenus, Ulmus subg. Indoptelea, is described. It can be recognized morphologically by its combination of compact inflorescences with very short pedicels, and samaras with narrow, strongly ciliate wings. It is sister to Ulmus subg. Ulmus, but has a smaller genome than either of the other subgenera.

Bazzania amadoi is a new species described and illustrated here based on material collected during a study of the bryophyte flora in the Brazilian Amazon Mountains, Monte Roraima National Park, Roraima State, Brazil. Bazzania is the largest genus of Lepidoziaceae, with ca. 30 species recognized in South America. A combination of leaves slightly bifid and recurved to the ventral side, underleaves imbricate and connate with the leaves on only one side, and vittae absent with only a region of larger leaf cells in the mid-lower portion of the leaves (vitta-like), distinguishes B. amadoi from the similar B. gracilis. The new taxon is placed within the key for the identification of species from the Brazilian Amazon domain, and represents an addition to the rich endemic flora of the Brazilian Amazon mountains of the Guiana Highlands. A detailed illustration of the new species is included, and also its informal conservation assessment.

Machupicchu Historical Sanctuary is a natural protected area that bears a considerable orchid diversity. Masdevallia is one of the most common, showiest, and distinctive genera among Machupicchu orchids, where six species are currently known. Here, we describe a new species of Masdevallia from Machupicchu, which we name Masdevallia bastantei. The species is similar to M. karineae but differs in the long flowers of 12 to 17 cm in length and a campanulate, incanous, maculate sepaline tube. We provide a description and illustrations of this new species. Furthermore, we present pictures and a key including all Masdevallia species that occur within the Machupicchu Historical Sanctuary.

Two new fern species from Sarawak, Antrophyum hovenkampii and Pteris hovenkampii are described in memory of renowned pteridologist, Peter Hans Hovenkamp. Their relationships are inferred using morphological comparisons and molecular phylogenetic analyses. A description, photographs of key characters, distribution map, and habitat description of both new species are provided. Keys to all known species of Antrophyum and Pteris in Borneo are also included.

Tetrastigma loheri (Vitaceae) is a vine species native to Borneo and the Philippines. Because it is a commonly encountered forest species in the Philippines, T. loheri is potentially suitable for studying patterns of genetic diversity and connectivity among fragmented forest ecosystems in various parts of this country. However, previous research suggests that T. loheri is part of a species complex in the Philippines (i.e. the T. loheri s. l. complex) that potentially also contains Philippine plants identified as T. diepenhorstii, T. philippinense, T. stenophyllum, and T. trifoliolatum. This uncertainty about its taxonomic delimitation can make it challenging to draw conclusions that are relevant to conservation from genetic studies using this species. Here, we tested the hypothesis that T. loheri s. l. is composed of more than one species in the Philippines. For this, we used generalized mixed Yule coalescent (GMYC) and Poisson tree process (PTP) species delimitation models to identify clades within DNA sequence phylogenies of T. loheri s. l. that might constitute species within this complex. Although these methods identified several putative species, these are statistically poorly supported and subsequent random forest analyses using a geometric morphometric leaf shape dataset and several other vegetative characters did not result in the identification of characters that can be used to discriminate these putative species morphologically. Furthermore, the results of principal component and principal coordinates analyses of these data suggest the absence of morphological discontinuities within the species complex. Under a unified species concept that uses phylogenetic and morphological distinction as operational criteria for species recognition, we therefore conclude that the currently available data do not support recognizing multiple species in the T. loheri s. l. complex. This implies that T. loheri is best considered as a single, morphologically variable species when used for studying patterns of genetic diversity and connectivity in the Philippines.

We present a monographic treatment for the 13 species of Elaphoglossum sect. Polytrichia subsect. Apoda (Dryopteridaceae). Molecular phylogenetic analyses have recovered this subsection as monophyletic within the so-called “subulate-scaled clade” of Elaphoglossum. Morphologically, the species of E. subsect. Apoda are usually characterized by the presence of brightly colored stem scales (yellowish, orangish, or reddish, as opposed to castaneous to black), evenly distributed subulate scales on laminar surfaces, tiny glandular hairs on different parts of the leaves, and adult sterile leaves without hydathodes. The species can be divided into two groups: one with subsessile and the other with long-petiolate leaves. Elaphoglossum subsection Apoda is distributed from southern Mexico and the Antilles to Bolivia and midwestern Brazil. Elaphoglossum atehortuae, a new species from the Amazon region of Ecuador, is described, illustrated, and compared to its most similar species. It is unusual within this group for lacking subulate scales on both surfaces of the laminae, a character state that it shares with E. backhouseanum. Two species, E. polyblepharum and E. trichophorum, are included in the group for the first time, whereas E. procurrens and E. siliquoides are excluded based on morphological characters and previously published molecular phylogenies. We also provide comments for E. ×morphohybridum, which is a hybrid between E. alvaradoanum and E. crinitum. Lectotypes are designated for Acrostichum apodum, A. platyneuron, A. cubense, A. procurrens, A. trichophorum, and Elaphoglossum auripilum, and epitypes are designated for A. apodum. To facilitate the identification of species, we provide keys, descriptions, illustrations, comments, synonyms, distribution maps, spore images, and a list of specimens examined.

Habenaria longissima, a new species from the H. nuda species complex, is described and illustrated. It is remarkable for the exceptionally long lateral segments of the petals and labellum, which are the longest among Neotropical Habenaria, both in absolute and in proportional terms. Despite the morphological similarity, Bayesian and parsimony phylogenetic analyses based on nuclear (ITS) and plastid DNA markers (matK), revealed that H. longissima is distantly related to other species of the complex, and constitutes an independent lineage. Its distribution is unusual in that it is the only species of Orchidaceae restricted to the Quadrilátero Ferrífero in the State of Minas Gerais and to Chapada Diamantina, in the central part of the Espinhaço range in the State of Bahia, with the populations 1000 km from each other. Habenaria longissima is a rare species, known only from three localities and four populations and informally proposed as Endangered due to the small area of occupancy and small number of known populations.

Oenothera sect. Pachylophus has proven to be a valuable system in which to study plant-insect coevolution and the drivers of variation in floral morphology and scent. Current species circumscriptions based on morphological characteristics suggest that the section consists of five species, one of which is subdivided into five subspecies. Previous attempts to understand species (and subspecies) relationships at a molecular level have been largely unsuccessful due to high levels of incomplete lineage sorting and limited phylogenetic signal from slowly evolving gene regions. In the present study, target enrichment was used to sequence 322 conserved protein-coding nuclear genes from 50 individuals spanning the geographic range of Oenothera sect. Pachylophus, with species trees inferred using concatenation and coalescent-based methods. Our findings concur with previous research in suggesting that O. psammophila and O. harringtonii are nested within a paraphyletic Oenothera cespitosa. By contrast, our results show clearly that the two annual species (O. cavernae and O. brandegeei) did not arise from the O. cespitosa lineage, but rather from a common ancestor of Oenothera sect. Pachylophus. Budding speciation as a result of edaphic specialization appears to best explain the evolution of the narrow endemic species O. harringtonii and O. psammophila. Complete understanding of possible introgression among subspecies of O. cespitosa will require broader sampling across the full geographical and ecological ranges of these taxa.

Three new species of Microlicia endemic to Serra do Cipó, Minas Gerais state, Brazil, are described here. Microlicia joaosemiriana and M. longiglandulosa are characterized by their sessile leaves, congested flowers at the apex of the branches, dimorphic stamens with tetrasporangiate and bicolorous anthers. However, M. joaosemiriana differs in having hypanthium and sepal covered only with spherical glands and sepal shorter than the hypanthium length. Microlicia longiglandulosa has hypanthium and sepal with glandular trichomes mixed with spherical glands and sepal longer than the hypanthium length. Microlicia jolyana has a petiolate and thickened leaf, lanceolate to oblong leaf blade, rounded to slightly acuminate at the apex, smooth and not striate hypanthium surface, triangular-oblong and thickened sepal, dimorphic stamens, and purple to purple-blackish anther on both whorls. Also, Microlicia linifolia var. naudiniana is elevated to species rank with a new name (Microlicia acerosa), and M. nortecipoana and M. petiolulata are synonymized under M. hirtoferruginea. Additionally, we provide an updated checklist of Microlicia species in the Serra do Cipó.

Senna (Leguminosae, Cassiinae) is a speciose genus widely distributed throughout tropical and subtropical regions of the world. During taxonomic studies of Senna sect. Chamaefistula ser. Bacillares, a new endemic and endangered species from the Atlantic Forest of Bahia, Brazil was discovered. The new species, Senna bahiensis, is compared with its morphologically similar species Senna gardneri, including x-ray analysis comparison of their leaflet venation patterns. The use of high resolution x-ray digital images provided the decisive information, being a promising technique to be used in systematic studies.

Comolia abaetensis, an endemic new species from the Abaeté and Itapuã sand dunes, Bahia, Brazil, is described and illustrated. Additionally, field images and a geographic distribution map of the new species are provided, together with morphological and leaf anatomy comparisons among the most similar congeners, and a dichotomous key to the species that occur in Brazil. Comolia abaetensis is morphologically similar to C. ovalifolia, but differs from the latter by the following combination of characteristics: glabrous (rarely with sparse trichomes) internodes and hirsute nodes, glabrous leaf blades or rarely with sparse eglandular trichomes, abaxial surface predominantly red with green nuances, glabrous pedicels, cupuliform hypanthium, and filaments of the antesepalous stamens that are 5–6 mm long. Specimens of C. abaetensis have been confused with and/or tentatively determined as C. berberifolia. However, these two species are readily distinguished by the size of the leaves, the length of the trichomes and filaments, and the color of the abaxial foliar surfaces. Comparisons between the leaf anatomy of C. abaetensis and C. ovalifolia are provided and the occurrence of emergences and hydathodes are here reported for the genus for the first time. Finally, we informally recommend a conservation status of Critically Endangered [CR B1ab (iv) + 2ab (iv)] for C. abaetensis.

The new species Staelia schumannii was discovered through the analysis of historical collections associated with Staelia thymbroides (≡ Psyllocarpus thymbroides). The rediscovery of the missing type of S. thymbroides has shed light onto its identity, as well as onto the yet undescribed S. schumannii. In order to clarify their circumscriptions, both species are described and illustrated, and an identification key for all Brazilian Staelia is provided.

Neocalyptrocalyx (Capparaceae) is a Neotropical genus that comprises eleven species that occur in the lowlands of Brazil, Guyana, French Guyana, Suriname, Venezuela, and Ecuador. The study of collections deposited in herbaria added to field observations allowed the recognition of three species as new to science, and those are formally presented here: Neocalyptrocalyx aequatoriensis, known only from eastern Ecuador, Neocalyptrocalyx atlanticum from the Atlantic Forest, and Neocalyptrocalyx polycataphyllus from the Brazilian Amazonia. Neocalyptrocalyx aequatoriensis represents the new westernmost boundary for the genus and the first generic record for Ecuador. We present diagnoses, descriptions, ink illustrations, field photos, distribution maps, notes on ecology, habitat, morphology, phenology, conservation status, and a key to distinguish the new species from related species.

The palm tribe Lepidocaryeae (Arecaceae) comprises seven genera and 51 currently accepted species that are distributed in lowland tropical forests and savannas across Africa and the Americas. Subtribal relationships within Lepidocaryeae have been a persistent challenge, limiting our understanding of its systematics, morphology, and biogeography. Several aspects make the tribe an ideal system to study plant evolution and diversity: it is well-represented in the fossil record as a prolific pollen producer, its continental diversity contradicts common biodiversity patterns of lower species richness in Africa in comparison to South America, and it contains one of the most abundant Amazonian tree species, Mauritia flexuosa. Here, we investigated the systematics of the tribe by sampling 122 individuals representing 42 species (82% of the tribe), using target sequence capture. We recovered nearly 10,000 single nucleotide polymorphisms from nuclear and plastid DNA across 146 target sequences to separately infer a phylogenomic tree. Our results strongly support inter-generic and inter-specific relationships, where a majority of nodes were resolved with over 90% bootstrap support. We also identify strong phylogenetic support for the recognition of a new species from central and south Amazonia, Mauritiella disticha. The distichous phyllotaxy is diagnostic of the species within the genus. Rare and currently only known from the middle-lower Madeira River basin in the state of Amazonas, Brazil, M. disticha is restricted to open vegetation and forest edges growing in white sand habitats with saturated or well-drained soils. Our preliminary red list assessment suggests its threatened status to be vulnerable (VU). We use our phylogenomic inference to define and contextualize systematic relationships in the tribe, and present a formal species description.

Planchonella (Sapotaceae) in Hawaii has a complicated taxonomic history that has resulted in considerable confusion among botanists and conservation practitioners. Up to seven different species and several varieties have been described in Hawaii, with the most recent taxonomic evaluation recognizing one species, P. sandwicensis. We have conducted a phylogenetic study of Hawaiian Planchonella using molecular (ETS, ITS, and RPB2) and morphological data to infer whether one or several species can be distinguished. In line with earlier research based on molecular data, we find that Planchonella in Hawaii is comprised of two well-supported clades distinguished by fruit color: yellow or purple. The purple-fruited clade contains individuals with flat leaf blades, long pedicels, and greenish corollas, a species corresponding to P. sandwicensis, distributed on all Hawaiian Islands except the island of Hawaii. The yellow-fruited clade possesses leaves that are frequently longitudinally rolled, wavy or distally deflexed, short pedicels, and yellow or cream (rarely greenish) corollas, a species corresponding to P. spathulata that is distributed on all Hawaiian Islands but is believed rare in Kauai. Both species can set fruit with aborted ovules, resulting in small fruits that look dissimilar to well-developed fruit. The species can occur in sympatry, where P. sandwicensis seems to be better adapted to slightly wetter forests and higher altitudes, whereas P. spathulata usually occurs at lower elevations in mesic to dry forests. Both species exhibit large morphological variation and overlap, resulting in many previous collections with inadequate label information, which has impeded correct taxonomic determinations. We refrain from recognizing infraspecific taxa because there is no morphological coherence, no molecular support, and it is unhelpful for species conservation. Five lectotypes are here designated. Both species are assessed for conservation status according to IUCN guidelines and are tentatively proposed as species of Least Concern.