The taxonomy of the Polypodiaceae subfamily Microsoroideae is highly problematic, especially with respect to the circumscription of the highly variable and non-monophyletic genus Microsorum. Using phylogenetic analyses and morphological evidence, we demonstrate that sixteen taxa typically treated in the genera Microsorum and Colysis are not closely related to those groups and instead belong to three clades that are successive sister groups to the Old-World ant-fern genus, Lecanopteris. We use the available genus name Dendroconche for one of these clades and propose the new genera Bosmania and Zealandia to accommodate the remaining two groups. We provide a description and identify morphological synapomorphies for each of the genera, make new combinations and designate lectotypes where necessary, and present keys and descriptions for all relevant species. We also discuss the evolution of ant-fern associations in the lecanopteroid ferns and highlight the need for additional taxonomic work in the subfamily. The following new combinations are provided: Bosmania lastii, B. leandriana, B. membranacea, Dendroconche ampla, D. latilobata, D. linguiforme, D. sayeri, D. scandens, D. varians, Zealandia novae-zealandiae, Z. powellii, Z. pustulata, Z. pustulata subsp. howensis, and Z. vieillardii.

Hymenophyllum subg. Mecodium, composed of the taxonomically notorious H. polyanthos and approximately 15 other closely related taxa, is a common element of filmy fern communities in the tropical and subtropical moist forests. In Taiwan, although only H. polyanthos and one or two closely related taxa were recognized in recent studies, considerable morphological variation has been observed among populations throughout the island. Thus, we conducted an extensive morphological investigation, as well as a molecular phylogenetic analysis, to clarify the specific diversity and phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan. Field and herbaria surveys helped in recognizing five morphs in Taiwan, mainly differentiated by the combination of certain traits, viz., the presence or absence of stipe wings, general frond size and shape, degree of laminar crispation, sori position, and involucre shape. The different morphs had diverse ecological preferences. The phylogenetic tree, inferred from the sequences of the plastid loci rbcL and rps4-trnS, demonstrated that Hymenophyllum subg. Mecodium materials in Taiwan comprise several well-supported lineages, mostly corresponding to the classification based on morphology. Comparing with the protologues and type specimens of 34 related scientific names, the five morphs are herein recognized as five independent species. A new species, Hymenophyllum exquisitum, is described here. Also, the status of H. paniculiflorum is reconfirmed and that of H. fujisanense, H. parallelocarpum, and H. punctisorum reinstated. Only H. exquisitum and H. parallelocarpum are endemic to Taiwan among all the species studied. In addition, the names Hymenophyllum blumeanum, H. integrum, H. microsorum, H. polyanthos, H. tenellum, and H. wrightii are now excluded from the regional flora, and several related taxa from China, Taiwan, and the Philippines are treated as synonyms. This study unravels the deep phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan and Eastern Asia.

We describe a new species of Stegnogramma (Thelypteridaceae; Polypodiales) as Stegnogramma australis. Morphologically, it is most similar to S. griffithii, sharing the character of pinnate fronds with ternate terminal pinnae. However, S. australis can be distinguished from S. griffithii by having more free pinna pairs, shorter distal stipe hairs, and fewer included veinlets in the laminar areoles. A description, photographs of key characters, and the known distribution of the new species are presented. We also infer genome size and reproductive mode of the new species using flow cytometry. In addition, the occurrence of S. aspidioides in Vietnam is confirmed and a key to all known species of Stegnogramma in Vietnam is given.

A new Habenaria species from the state of Mato Grosso is described and illustrated. Habenaria gracilisegmenta was discovered in campinarana understory, in northern Mato Grosso state, on the southern edge of the Brazilian Amazon. The species is distinguished by its slender habit, and by the few, delicate flowers, with very long, thin lateral petals and lip segments. Its morphological affinity with other Neotropical species is unclear. A molecular phylogenetic analysis revealed that the new species does not belong to any of the Neotropical subclades of the genus, constituting an additional lineage. The species is one of two of the genus endemic to the Brazilian Amazon, and considered threatened given the small number of known populations and restricted distribution.

A new species of Dichorisandra from the Brazilian Atlantic Forest is herein described, illustrated, and compared to morphologically similar species. Dichorisandra striatula is characterized by leaf blades with small and discontinuous white stripes on the adaxial surface, hirsutulous indumentum on both surfaces, obovate to broadly obovate petals, and ellipsoid fruits. Information on phenology, habitat, conservation status, and a geographical distribution map are also provided.

Araeococcus lageniformis is a new species described and illustrated here based on collections from the Atlantic Forest from the south of Bahia State, northeastern Brazil, and on morphological and anatomical characters. It is distinguished from A. nigropurpureus by the diameter of the tank, the morphology of the leaf, floral bracts, and sepals, by its sessile to nearly sessile flowers, its seed morphology, and by the presence of trichomes on both sides of the leaves. So far, the species is only known from Apuarema and Ibirapitanga municipalities. The type population was found in an unprotected area, fragmented by tracks and roads, where illegal logging takes place. Here we preliminarily assessed its conservation status as critically endangered.

Subtribe Chusqueinae was previously composed of the genera Neurolepis and Chusquea. Following molecular-based phylogenetic studies, all species of Neurolepis were transferred to Chusquea and placed in two new subgenera: Chusquea subg. Magnifoliae and Chusquea subg. Platonia. Complete keys for the identification of taxa within C. subg. Magnifoliae and C. subg. Platonia are lacking. The present paper provides five new reports and a taxonomic revision of Chusquea subg. Magnifoliae and C. subg. Platonia in Peru involving 13 taxa. Vegetative and reproductive morphological diagnostic characters were analyzed. Complete illustrations of C. aristata, C. fimbriligulata subsp. peruviana, and C. spectabilis are provided. Chusquea elata, C. fimbriligulata subsp. fimbriligulata, C. mollis, C. nana, and C. spectabilis constitute new reports for Peru. Keys for the identification of the species of Chusquea subg. Magnifoliae and C. subg. Platonia occurring in Peru were prepared based on vegetative and reproductive characters and are here presented for the first time.

Unifoliolate leaves are relatively rare in the species-rich dalbergioid clade of papilionoid legumes (Leguminosae, Papilionoideae). For the pantropical, diverse genus Aeschynomene (ca. 180 species), the only known record of unifoliolate species described so far is the savanna-inhabiting A. simplicifolia from Chapada dos Veadeiros in Goiás, Brazil. The current work provides a description, illustrations, and a distribution map of another unifoliolate species, Aeschynomene chicocesariana, which was newly discovered in the rupestrian grasslands of Chapada Diamantina in Bahia, Brazil. Bayesian phylogenetic analyses of DNA sequence data (nuclear ribosomal ITS/5.8S and the plastid genes matK and trnL intron) have unequivocally placed A. chicocesariana with the rest of Aeschynomene species that are traditionally placed within Aeschynomene sect. Ochopodium. This result agrees with the shared morphology of A. chicocesariana and members of that section.

Taxonomic and ecological knowledge of plant species complexes informs their conservation status. Poorly delimited species boundaries can lead to incorrect assessments of biodiversity, and a rare species might have its distribution range overestimated if considering other closely related taxa as the same one. The present study investigates the level of morphometric variation within the Abarema cochliacarpos complex throughout its entire distribution range in the Brazilian Atlantic Forest and Caatinga vegetation, and considers the drivers of this variation. A morphometric study using cluster, PERMANOVA, and NMDS analyses was conducted. We analyzed patterns of trait variation among and within populations, and their relationship with environmental factors along with their geographical gradient. From the four morphotypes previously cited for the complex, the analyses delimited three morphological groups. Their morphological characteristics differed in response to environmental drivers. We identified morphological characters that differentiated the groups within the complex. The development of conservation strategies and actions to fully protect a species complex requires the understanding of the morphological variation within the complex. In the Abarema cochliacarpos complex different threats and challenges are associated with the conservation of each morphotype. We highlight the importance of conserving the various morphotypes of a species complex which has a large distribution range as evolutionary significant units, something that is frequently neglected in the published literature.

A new species of Bernardia with stellate trichomes from the Brazilian Cerrado is described and illustrated. Bernardia allemii is most similar to B. gardneri, but differs by its multi-stemmed, subshrub habit, broader leaf blades, tomentose old branches, staminate bracteoles that are usually reniform to flabellate, and larger sepals and bracts in the pistillate flowers. Photographs, a distribution map, information about the conservation status of the new species, and a key to the species with stellate trichomes in Brazil are also provided.

A new species of Dalechampia from southeastern Brazil, belonging to Dalechampia sect. Dioscoreifoliae, is described and illustrated here. Dalechampia margarethiae is a twining vine occurring exclusively in Espírito Santo state. Its pseudanthia are similar to those of D. peckoltiana and D. pentaphylla, but D. margarethiae differs in a set of important characters, including having cylindrical, down-curved style tips, staminate flowers at anthesis having unreflexed sepals with stamens born on unelongated columns, whitish floral resin, and simple, entire, cordate leaves.

Two new species of Turnera (Passifloraceae s. l., Turneroideae), T. acangatinga and T. ibateguara, from the Atlantic Forest of northeastern Brazil, are described. Some specimens of T. acangatinga were originally treated as T. annularis. Turnera ibateguara was recently considered part of T. pernambucensis, a species which also occurs in the Atlantic Forest in northeastern Brazil, and which was, until then, only known from the type material. In this study, recent collections of T. pernambucensis in the state of Alagoas revealed that both are distinct species and that have been mistakenly identified so far. We provide data on morphology, distribution, habitat, and phenophases, a preliminary conservation status assessment for the three species, and a key to the species with capitate inflorescences from Alagoas and Pernambuco.

Fritzschia atropurpurea, an endemic new species from the Serra do Cipó, Espinhaço Range, Minas Gerais state, Brazil, is described and illustrated. This new species can be easily differentiated from its congeners by the combination of the following characters: hirsute-glandular trichomes covering the branches, petioles, leaves, bracteoles, pedicels, hypanthium, sepals, and the medial-apical portion of the right margin of the petals; membranaceous leaves with a dark purple abaxial surface; and long pedicels. Images from scanning electron microscopy, photos of the species in the field, a distribution map, and a key to identify the congeners that occur in the Serra do Cipó are presented. We suggest that if a formal assessment were performed, Fritzschia atropurpurea would probably be categorized as an Endangered (EN) species.

Monteiroa rubra is described as a remarkable new species from Rio Grande do Sul, Brazil. It is notably distinct from the other ten species of Monteiroa. The new species is morphologically most similar to the four species of the genus with unlobed leaves that also lack cordate leaf bases. Monteiroa rubra apparently is an endemic species known from three localities in wetlands associated with grasslands in Augusto Pestana and Fontoura Xavier municipalities in southern Brazil. A morphological description, distribution map, photographs, ecological notes, and a key to morphologically most similar species are presented. According to IUCN criteria, if a formal assessment were performed, the new species would probably be considered Endangered.

Stellaria (Caryophyllaceae, tribe Alsineae) is a cosmopolitan genus of herbaceous plants that heretofore has lacked a stable estimate of total number of species. Here, we attempted to sample all species currently recognized under the name Stellaria to determine which belong to a core Stellaria genus versus which are masquerading under this name and are instead more closely related to one of several outgroup lineages. Phylogenetic relationships inferred with RAD loci were recovered with generally high levels of support, regardless of age of specimens (here up to 98 yr) utilized for molecular work. Analyses resolved a monophyletic, core radiation of Stellaria that is sister to Cerastium and others. Within core Stellaria, of which we sampled ca. 87% of species, we recovered five primary lineages. However, current infrageneric hypotheses are incongruous with phylogenomic data, and most morphology-based infrageneric hypotheses break down in light of these results. Outside of core Stellaria we recovered numerous other species currently ascribed to Stellaria that are in need of revised generic placement. Based on current results, however, we propose several new taxonomic and nomenclatural renovations within core Stellaria and external to this group as contribution towards stabilization of generic boundaries in Alsineae. These modifications include description of a new genus of Caryophyllaceae from eastern Asia, Nubelaria, as well description of a new genus, Rabelera, to accommodate the lineage previously and more widely known as Stellaria holostea. Nine new combinations are proposed in the genera Adenonema, Cerastium, Mesostemma, Nubelaria, Rabelera, and core Stellaria. Additionally, one new status, one new synonymy, and lectotypes for four species are proposed. We estimate core Stellaria to consist of approximately 112 species, a decrease from many other published species counts. Our results lay a robust foundation for future evolutionary, phylogenetic, and morphological comparisons within Stellaria and among relatives.

Recent phylogenetic analysis circumscribes the bounds of a core genus of Stellaria comprising five major extant clades and around 112 species. Some finer scale phylogenetic relationships emerging from that study are interpreted here. The Larbreae and Petiolares clades are the main foci, as they comprise the bulk of Stellaria diversity. In particular, I address the implications of our phylogenetic work on some widespread and morphologically complex lineages of starworts, including the Stellaria borealis, Stellaria cuspidata, Stellaria longipes, and Stellaria media groups, and also briefly discuss other subclades within the Larbreae and Petiolares clades. Based on phylogenetic evidence, Stellaria sitchana is here recognized as a distinct species from Stellaria borealis rather than as Stellaria borealis subsp. sitchana, and this lineage is furthermore reported from the southern hemisphere for the first time. Other newly discovered lineages that require revised nomenclatural concepts pending future work also are briefly treated. Overall, a picture of widespread evolutionary parallelism emerges within Stellaria, and this parallelism is largely responsible for the non-monophyletic nature of most previous subdivisions of the genus.

We describe and illustrate Besleria discreta, a new species from the Brazilian state of Espírito Santo. The new species has been found in a mountainous area in the southern part of the state and can be recognized by leaf blades that are slightly bullate on the adaxial surface and a short corolla. We also report the occurrence of two species that have not previously been recorded in the Amazon rainforest in Brazil: Besleria concinna and Besleria neblinae. Data on morphology, ecology, distribution, and preliminary conservation status of the three taxa are also provided.

Adenocalymma is a genus of Neotropical lianas, shrubs, and treelets that belongs to tribe Bignonieae (Bignoniaceae). The genus is recognized by the cupular trichomes found on the prophylls, bracts, bracteoles, calyces, and fruits, and the presence of articulated petioles and petiolules. A recent molecular phylogeny of Adenocalymma recovered all three species of Neojobertia as well as Pleonotoma albiflora nested within the genus, indicating the need for an updated circumscription. Molecular phylogenetic results combined with morphological data also revealed the need for a revised circumscription for several species. Here, we present an updated circumscription and synopsis of Adenocalymma that recognizes 76 species within the genus. New combinations are proposed for N. alboaurantiaca, N. candolleana, and N. mirabile. Lectotypes are proposed for A. longeracemosum, A. nodosum, and A. validum, a neotype is proposed for A. paucifoliolatum, and an epitype is designated to support the lectoype of A. trifoliatum. In addition, twelve new synonyms are proposed as follows: 1) A. croatii is synonymized under A. biternatum; 2) A. aspericarpum is synonymized under A. cladotrichum; 3) A. fruticosum is synonymized under A. hyposticum; 4) A. apterospermum is synonymized under A. marginatum; 5) A. campicola is synonymized under A. nodosum; (6, 7, 8) A. axillare, A. bipinnatum, and A. paucifoliolatum are synonymized under A. peregrinum; 9) A. involucratum is synonymized under A. pubescens; 10) A. reticulatum is synonymized under A. scabriusculum; 11) A. pseudopatulum is synonymized under A. schomburgkii; and 12) A. prancei is synonymized under A. subincanum.

Isodon hsiwenii, a new species from Yunnan in Southwest China, is here described and illustrated. In order to clarify the phylogenetic placement of the new species within Isodon, Bayesian and maximum likelihood analyses based on two nuclear ribosomal DNA regions and four plastid DNA regions for 71 Asian Isodon species were conducted. The results indicate that I. hsiwenii is a member of the largest and poorly resolved Clade III, as sister species of I. hirtellus. Isodon hsiwenii can be distinguished from I. hirtellus by various morphological differences.

Solanum adamantium is described from Serra de Grão Mogol, located in the Espinhaço range, in northern Minas Gerais State, Brazil. The new species is ecologically and morphologically similar to the prickly species S. buddleiifolium and S. thomasiifolium, from which it differs in a series of vegetative and reproductive characters. We discuss the morphological similarities and differences among these species, as well as certain aspects of the new taxon's ecology and geographic distribution. Images of diagnostic characters, a map of geographical distribution, a preliminary conservation assessment, and full specimen citations are provided.

Doellingeria and Eucephalus form the earliest-diverging clade of the North American Astereae lineage. Phylogenetic analyses of both nuclear and plastid sequence data show that the Doellingeria-Eucephalus clade consists of two main subclades that differ from current circumscriptions of the two genera. Doellingeria is the sister group to E. elegans, and the Doellingeria + E. elegans subclade in turn is sister to the subclade containing all remaining species of Eucephalus. In the plastid phylogeny, the two subclades are deeply divergent, a pattern that is consistent with an ancient hybridization event involving ancestral species of the Doellingeria-Eucephalus clade and an ancestral taxon of a related North American or South American group. Divergence of the two Doellingeria-Eucephalus subclades may have occurred in association with northward migration from South American ancestors. We combine these two genera under the older of the two names, Doellingeria, and propose 12 new combinations (10 species and two varieties) for all species of Eucephalus.

Great Smoky Mountains National Park is renowned as one of the most biologically diverse tracts of land in North America and is the most visited national park in the United States. The park comprises ∼830 square miles, epitomizes eastern temperate hardwood forests of North America, and serves as a refuge for nearly 20,000 documented species from microbes to plants and mammals. Lichens comprise one particularly diverse group of organisms in the park. In this study, we review data from our 11 years of lichenological research in Great Smoky Mountains National Park. Based on approximately 6,000 new field collections generated, the park checklist now includes 920 species, a 129% increase over estimates made two decades ago. Nearly a quarter of the lichens reported in the park are known from only a single occurence whereas only 7% of the lichens are known from 20 or more occurences. An assessment of commonness/rarity for all 920 species indicates that nearly half of the park's lichens should be considered to be infrequent, rare, or exceptionally rare. We assessed the distributions of all 920 species and found that 54 are endemic to the southeastern United States, 30 are endemic to the southern Appalachians, and eight occur nowhere else than within the confines of the national park. We discuss biogeographical affinities of the park's lichen biota as a whole, delimiting six regional “floristic” connections. Our 11 years of research have resulted in the discovery of several species presumed to be extinct or near-extinct. We make one new combination (Fuscopannaria frullaniae) and describe five species as new to science, each commemorating National Park Service staff instrumental to the completion of the study: Heterodermia langdoniana, Lecanora darlingiae, Lecanora sachsiana, Leprocaulon nicholsiae, and Pertusaria superiana.