A systematic revision of the tropical moss genus Papillaria was carried out by combining morphological studies with phylogenetic reconstructions based on molecular data from the plastid (trnL-F and rpl16) and the nuclear (ITS region) genomes. For the morphological study a set of qualitative and quantitative features was studied in over 2800 herbarium specimens, including the types, of all 55 previously accepted species in the genus. After revision, nine species of Papillaria were recognized, Papillaria crocea and P. flexicaulis which are broadly distributed in the tropics, P. africana that is endemic to Africa, P. laevifolia that is known from the Americas, and P. flavolimbata, P. funiformis, P. leuconeura, P. nitens, and P. zeloflexicaulis that are known from Australia and the Pacific Islands. The majority of the other previously accepted names do not belong to Papillaria s. s. but to the closely related genera Toloxis and Meteorium. We propose five new synonyms under P. africana as well as one new synonym for P. crocea and one for P. laevifolia. The revision reduced the number of Papillaria species in Africa from ten to one and in South America from thirteen to three. We extend the geographic range of P. crocea due to a new record from eastern South America (Brazil).

Morphological studies and molecular phylogenetic analyses were carried out to assess the taxonomic status of Hymenophyllum caudiculatum, a species with a disjunct distribution in South America. The species is found in tropical and subtropical forests of Brazil and in temperate forest of southern Argentina and Chile. Based on the results of morphological, molecular, and species delimitation analyses, Hymenophyllum caudatum of the Valdivian forest of southern Chile and Argentina is proposed as a species separate from H. caudiculatum, endemic to Brazil. The two taxa are delimited, respectively, as follows: 1–5 cm long non-alate stipes (vs. 0.3–1 cm long non-alate stipes in Brazilian H. caudiculatum); stipe wings gradually ending (vs. stipe wings abruptly ending very near the rhizome); margin entire to somewhat undulate (vs. margin undulate to crispate); soriferous segment alate, angustate, or null (vs. soriferous segment with laminar constriction at apex); and widely obovoid receptacle with sessile sporangia (vs. flattened obovoid or globose receptacle with shortly pedunculated sporangia). Descriptions for the two species recognized here and a map of their geographical distribution are provided, along with nomenclatural revision, illustrations, and conservation status assessments.

A new species, Antrophyum nambanense, is described here based on the evidence from morphology and molecular phylogeny. Morphologically, short taeniform soral paraphyses and large fronds are the diagnostic characteristics of A. nambanense. Phylogenetically, it is most closely related to A. annamense, but can be readily distinguished from A. annamense by taeniform soral paraphyses (vs. filiform). We suggest A. nambanense is an allopolyploid of hybrid origin involving A. annamense and A. henryi, based on the evidence of morphology, phylogenetic position, chromosome number, and partially malformed spores. A description, photographs of key characters, distribution, conservation status, and ecology of the new species are presented. In addition, A. nambanense is also the first confirmed species with chlorophyllous spores in Antrophyum. Lastly, an updated key to all known Antrophyum species in Vietnam, including A. henryi as a new record for the country, is provided.

Cryptanthus cinereus D.M.C. Ferreira & Louzada, a new rare species of Bromeliaceae restricted to northeastern Brazil, is described and illustrated. Cryptanthus cinereus is a rupicolous plant that occurs in the Atlantic Forest on the top of a rocky outcrop and is known only from a single record. This new species is morphologically similar to Cryptanthus felixii, but differs mainly by its narrowly triangular leaves that are wider at base, primary bracts with adaxial surfaces densely lepidote (vs. glabrous or glabrous with base densely lepidote), shorter flowers (39–52 mm), sepal lobes lanceolate, with shorter connate sepals (1.6–5 mm) and petals (1–1.2 mm). An identification key to Cryptanthus cinereus and other species that occur in the Atlantic Forest north of the São Francisco River is provided. In addition, two species complexes are characterized for the area.

The genus Hechtia includes 84 species, 79 of them present in Mexico. With 12 species (including those described herein), the Mexican state of Guerrero is the third most diverse in species. As a result of botanical explorations for the project Bromeliaceae of Mexico, we describe here five new species for science, all endemic to Guerrero: Hechtia elegans, H. ensifolia, H. medusae, H. platyphylla, and H. pycnostachya. The proposed species are compared with other morphologically similar taxa (H. caulescens, H. flexilifolia, H. glauca, H. hintoniana, H. laxissima, and H. pretiosa). Morphological descriptions, images, and a distribution map of the described taxa are included, as well as an identification key for all the species of Hechtia currently known from Guerrero.

The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (µ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

Neptunia windleriana, a new polyploid species of the pantropical genus Neptunia, is described and illustrated. This plant is endemic to the state of Bahia, Brazil, and is found in areas of Caatinga near the São Francisco River. Among the species occurring in Brazil, it is most similar to N. plena, a widespread species, by having a gland on the petiole, but it differs mainly by the number of pairs of pinnae and leaflets, shape of the spike in bud, and the size of the peduncles. It is morphologically distinct from all other species of the genus by the combination of prostrate subshrub habit, smaller leaves, shorter petiole and shorter rachis length, few-flowered, globose spikes, 10 stamens, and glabrous ovary. The presence of monocrystals in the bundle sheath cells of the bracts of N. windleriana is recorded here for the first time for the genus, together with the chromosome number (2n = 56 vs. 2n = 28, ∼52, 54, 56, 72, 78 for three other species of the genus occurring in Brazil), it can be also used to identify the species. The epidermis of the stipules, leaflet, and bracts of N. windleriana is uniseriate, with paracytic stomata. The vascular system has collateral arrangement with the vascular bundles covered by a sheath, with or without isolated monocrystals. Our data support earlier hypotheses that Neptunia has a base number of x₂ = 14 which seems to be a secondary basic number that originated from an ancestral stock with x₁ = 7 and underwent karyotypic evolution by polyploidy. A key to the Brazilian species of Neptunia as well as anatomical, cytogenetic, taxonomic, and geographic distribution data, ilustrations and photos are provided.

During his expedition to South America, Eduard F. Poeppig collected about 17,000 botanical specimens, of which three belong to Connaraceae. These specimens were used to describe more than 500 species in the three volumes of Nova Genera ac Species Plantarum. In the third volume, Poeppig (1845) described two new species of Connaraceae: Omphalobium rubrum (=Connarus ruber) and Connarus macrophyllus (=Pseudoconnarus macrophyllus). As Poeppig´s descriptions are not accompanied by a clear indication of type specimens, these two names were afterwards lectotypified. A revision of Poeppig′s collections, descriptions and illustrations indicates that the lectotype of Omphalobium rubrum needs to be corrected, and a second step of lectotypification is required for Connarus macrophyllus. By correcting a lectotype, a reestablishment is also proposed. Aside from the nomenclatural updates, this work expands the description of the two species published by Poeppig (1845) as well as the reestablished taxon, and illustrates and discusses their taxonomy and distribution.

We present a phylogenetic classification for Plukenetia (Euphorbiaceae, Acalyphoideae) based on morphology and molecular phylogenetic studies using nuclear (ETS, ITS, KEA1 introns 11 and 17, TEB exon 17) and plastid (matK, ndhF, psbA-trnH) DNA data. Plukenetia comprises 25 species divided into six sections, with three new sections and four new species described here. The circumscription of Plukenetia is unaltered from recent treatments and we continue to recognize Romanoa as distinct. The sections of Plukenetia correspond with the subclade system proposed by Cardinal-McTeague and Gillespie (2016): P1 = P. sect. Fragariopsis comb. et stat. nov.; P2 = P. sect. Penninerviae sect. nov.; P3 = P. sect. Plukenetia; P4 = P. sect. Angostylidium; and P5 = P. sect. Hedraiostylus + P. sect. Madagascarienses sect. nov. The sections are distinguished by a combination of leaf venation, staminate flower morphology, pistillate flower number, style morphology, fruit type, and seed size. Additionally, we describe three new species from South America belonging to sect. Penninerviae: Plukenetia brevistyla and Plukenetia megastyla from the Amazon basin and Plukenetia chocoensis from the Chocó Biogeographic Region of Colombia. The new Amazonian species are morphologically similar to P. brachybotrya but distinguished by their style shape and size. The new Colombian species is morphologically similar to P. penninervia but distinguished by its elongate basilaminar extrafloral nectaries, presence of abaxial laminar extrafloral nectaries, and longer inflorescences. We also describe a new species from sect. Plukenetia, Plukenetia sylvestris, which is found in central and southern Peru. This species is suggested to be the wild progenitor of the cultivated P. carolis-vegae, differing by its smaller seeds/fruits and fewer stamens. Molecular data, including a new ETS phylogeny sampling P. brevistyla, support our new taxa as distinct. Keys to the sections and species of Plukenetia are provided and we designate 12 new lectotypes for Plukenetia and Romanoa.

A new species of Eugenia from the Atlantic forest of Brazil is described and illustrated. Eugenia flavicarpa is restricted to the Floresta de Tabuleiro (lowland forests) of Espírito Santo state and is nested in Eugenia subg. Pseudeugenia. Considering all other species of the subgenus that occur in forest vegetation types of the Atlantic forest phytogeographic domain, Eugenia flavicarpa can be distinguished mainly by the combination of smooth leaves with indumentum on both surfaces, with two marginal veins, usually ramiflorous inflorescences, pedicels 4.5–9.7 mm long, flower buds 3.5–4 mm in diameter, and by the calyx lobes that are 2–3 mm long with rounded to obtuse apices. Morphological analyses were performed to explore the significance of quantitative diagnostic features between the new species and the closely related species, Eugenia farneyi. Notes on the habitat, distribution, phenology, and conservation status of Eugenia flavicarpa are provided, as well as a key for all species of Eugenia subg. Pseudeugenia from forest vegetation of the Atlantic forest phytogeographic domain.

We present a taxonomic revision of Dactylaena and Haptocarpum as part of a series of generic revisions and delimitation of Neotropical Cleomaceae. Two new species are described, Dactylaena boliviensis and D. zmarztyae, one new combination is made, D. monandra, four lectotypes are designated in Dactylaena, and a key to all species is presented. This is the first comprehensive revision of the now seven recognized species of Dactylaena and provides needed clarification of species boundaries, distributions, and diversity. Haptocarpum is maintained as a monotypic genus.

Hawaiian taxa of Chenopodium are tetraploids and are distinguished from other members of the circumglobally distributed genus by minute morphological characters. Because of these reasons, the geographic origin of Hawaiian Chenopodium has remained unclear. Across the Hawaiian Archipelago, taxa of Chenopodium are morphologically variable and grow in highly disparate xeric habitats, especially in terms of precipitation, temperature, wind, salt spray, and solar irradiation. Habitats include dry subalpine shrublands, sandy beach strands on atolls in the Northwest Hawaiian Islands, dry to mesic forests, and precipitously tall sea cliffs of northwestern Moloka‘i. From the Moloka‘i sea cliffs, which are battered by high energy winds, salt spray, and strong seasonal precipitation, we describe C. oahuense subspecies ilioensis as segregated from the widespread Hawaiian C. oahuense sensu lato. Morphometric analyses distinguish C. oahuense subsp. ilioensis by its strongly prostrate to scandent habit, thick succulent leaves, smaller average leaf size, limited lobing of the laminar margins, and smaller seeds. Phylogenetic analyses using two DNA regions (the plastid gene rpl32-trnL and nuclear ITS) of newly sequenced individuals of C. oahuense s. l. and C. oahuense subsp. ilioensis plus outgroup taxa support the monophyly of Hawaiian Chenopodium and reveal a geographic origin of temperate Eurasia. Two equivocal hypothetical scenarios are discussed regarding the likely sequence of events leading to the arrival of Chenopodium in Hawaiian Islands followed by possible in situ speciation of the Moloka‘i endemic C. oahuense subsp. ilioensis.

Species in the genus Coccoloba are trees, shrubs, and lianas present in low elevation tropical and sub-tropical forests. Since 1756, well over 400 taxa have been described for Coccoloba. Coccoloba species are natively distributed throughout the New World in a variety of habitats. Despite being distributed throughout the Neotropics, the concentration of Coccoloba species in a given area varies considerably, with four centers of diversity for the genus: southern and coastal Brazil, the West Indies, Mesoamerica, and Amazonia. We here present the first molecular phylogeny of Coccoloba and use this phylogeny to investigate geographic patterns of diversity within the genus. The topology of the phylogeny and the closest related genera to Coccoloba suggest a Mesoamerican origin for the genus. The South American species are recovered as the crown group of the phylogeny with one instance of a separate migration event from Mesoamerica to South America. Coccoloba species in Mesoamerica and the Caribbean show little to no geographic pattern to their diversification. Mesoamerica and the Caribbean are best considered as one phytogeographic region for Coccoloba.

Despite being dominant elements of understory communities in the coniferous forests of western North America, phylogenetic relationships among bilberries (Vaccinium section Myrtillus) remain unresolved. Morphological delimitation among most western bilberry species is tenuous, and traditionally employed molecular sources of phylogenetic information have yielded insufficient variability. Moreover, these species are hypothesized to have undergone extensive introgression. We used RADseq data analyzed with maximum likelihood species tree estimation and Patterson's D-statistic analyses to examine the influence of introgression on relationships among Vaccinium myrtillus, V. scoparium, and V. cespitosum. Additionally, we used these data to assess whether the populations of V. myrtillus disjunct between North America and Eurasia are monophyletic and should continue to be recognized as conspecific. Significant genome-wide introgression, as determined through D-statistic analyses, was detected between North American samples of V. myrtillus and V. cespitosum, and to a lesser extent, between V. myrtillus and V. scoparium. No significant D-values were detected between V. scoparium and V. cespitosum. Accessions of Vaccinium myrtillus from Eurasia and North America were recovered as non-monophyletic, prompting our proposed resurrection of V. oreophilum for North American material. The long-assumed sister species relationship between V. oreophilum and V. scoparium was not recovered in our analysis. Instead, V. oreophilum and V. cespitosum were inferred to be sister taxa. This study reveals considerable introgression detectable in the evolutionary history of western North American bilberries and demonstrates the utility of RADseq data to resolve species level relationships in groups that undergo reticulate evolution such as Vaccinium.

There has been great confusion between Spermacoce glabra, S. riparia, and S. tenuior since their original descriptions. These species can be distinguished mostly by their seed features. Clustering and principal coordinate analyses (PCoA) were used to scrutinize the formation of hierarchical non-overlapping groups strictly according to the degree of morphological similarity. Thirteen characters were scored for 26 herbaria specimens. The taxonomic identity of these three species is discussed. Redefined descriptions and illustrations are provided, especially for fruit, seed, and pollen characters. A map and a discussion of the updated geographical distribution of these species are included. A table summarizing the different taxonomic concepts in contemporary floristic studies and an identification key to all American Spermacoce species are also provided. The new combination Spermacoce affinis (DC.) R.M. Salas is presented here.

Randia heteromera is a new species described based on studies of taxonomy and vegetative anatomy (leaf, stipule, and colleters). This species is illustrated and diagnosed in comparison to the other four similar species of Randia in the Southern Cone of America. The species grows in areas of humid forests, locally known as the humid Chaco in the southern part of its distribution (Argentina and Paraguay), and in seasonal forests in the northern part, in northeast Paraguay and the south of Mato Grosso do Sul in Brazil. We present a key to distinguish R. heteromera from the other species of the Southern Cone of America. The species was also compared with similar taxa, Randia nitida or R. hebecarpa, occasionally used to identify material from the Southern Cone of America. A distribution map is provided. The anatomical data studied had a taxonomic value at the species level. In addition, based on the leaf anatomy studies carried out in the present study and in previous studies, three new types of vascular tissue organization in the leaf are described for Rubiaceae.

Xylophragma (Tribe Bignonieae, Bignoniaceae) includes seven species of lianas or scandent shrubs. The genus is characterized by leaves 1–5-foliolate with a simple tendril replacing the terminal leaflet, branched trichomes, calyx usually cuspidate, pink flowers, and ovary usually lepidote. The genus is distributed through dry forests from Mexico to Paraguay and Southern Brazil. We provide the first comprehensive taxonomic treatment for Xylophragma, including a detailed description of the genus, a key for all species, complete list of synonyms, descriptions and illustrations for all species, as well as information on the geographic distribution, habitat, phenology, conservation status, and taxonomic comments for all taxa. Overall, we analyzed more than 700 sheets deposited in 13 herbaria, including types for all accepted names and synonyms. We designate lectotypes for Arrabidaea clausseni, Arrabidaea elliptica, Arrabidaea macrophylla, Rojasiophyton tuberculatum, Saldanhaea myriantha var. pubescens, and a second step lectotype for Distictis rovirosana. Four new synonyms are proposed: A. claussenii as a synonym of X. corchoroides; S. pratensis and R. tuberculatum as synonyms of X. myrianthum; and X. unifoliolatum as a synonym of X. seemannianum.

Cuscuta californica complex (sensu lato, s. l.) is a western North American group of species in which the infrastaminal scales are reduced, making the morphological delimitation of species particularly challenging. A revision of this group was prompted by the discovery of an apparent new species from central California based primarily on molecular means. Driven by this finding, the morphological limits of C. californica s. l. species were comprehensively re-evaluated through a morphometric study. DNA sequences from plastid (trnL–F region and rbcL), nuclear ribosomal ITS and 26S rDNA, as well as a low-copy nuclear pentatricopeptide repeat (PPR) gene were used to reconstruct evolutionary relationships among taxa. Last but not least, the host range of relevant taxa was determined using herbarium specimens. Molecular results strongly supported the new species, C. difficilis, which was found to be morphologically separated from C. brachycalyx only by subtle calyx lobe and corolla tube shape differences. Despite sharing some of the hosts, all the members of C. californica s. l. exhibited a differentiation of their host ranges. An identification key and description of the new species were provided together with a discussion on the systematics and host range of C. californica s. l.. Hybridization, accompanied by plastid capture, was suggested as a possible mechanism of speciation for C. brachycalyx.

A new species of Ipomoea (Convolvulaceae), endemic to the Caatinga domain of northeastern Brazil, is described and illustrated. Ipomoea bonsai has often been misidentified as I. brasiliana or I. subincana in herbarium collections, probably due to the densely pubescent and brochidodromous leaves of all three species. The new species is a shrub, with unexpectedly robust stems and scandent branches. A diagnosis, with a complete morphological description, illustrations, taxonomic comments, conservation status, distribution map, and photographs are presented.

The number and identity of species within Euthamia (Asteraceae, Astereae) have varied considerably among taxonomic treatments. Euthamia graminifolia (L.) Nutt. is often treated broadly, including plants from the northern and eastern United States and Canada, including the Atlantic and Gulf Coasts. Broad-leaved, largely glabrous plants from New Jersey to the Florida Panhandle have been inconsistently treated as E. graminifolia, E. graminifolia var. hirtipes (Fernald) C.E.S. Taylor & R.J. Taylor, E. hirtipes (Fernald) Sieren, or a hybrid between E graminifolia and E. caroliniana (L.) Greene ex Porter & Britton. Similarly, plants from the Florida Panhandle to eastern Louisiana have been incorporated into E. graminifolia or E. graminifolia var. hirtipes with only Greene in 1902 recognizing these plants as a distinct species, E. scabra Greene. To determine the identity and proper rank of these entities, morphological and phylogenetic analyses were performed to evaluate relationships within Euthamia. Plants from the Atlantic Coast most morphologically resemble Gulf Coast plants which similarly resemble E. gymnospermoides Greene. The Gulf Coast plants and E. gymnospermoides share similar DNA sequences while the Atlantic Coast plants represent a unique clade. Neither Gulf Coast nor Atlantic Coast plants contain highly polymorphic sequences, indicating that they are not hybrids. Occasional plants found within southernmost Alabama and the Florida Panhandle have polymorphic sequences and intermediate morphology however, suggesting that putative hybrids exist between Gulf and Atlantic Coast plants. This study concludes that both entities deserve specific rank as E. scabra Greene for scabrous plants along the central Gulf Coast and E. hirtipes (Fernald) Sieren for largely glabrous plants mostly along the Atlantic Coast. Ecological niche modeling indicates that precipitation, especially during summer months, and soils, namely coarse fragments and sand content, drive the distribution of these organisms, largely restricted to either side of the Apalachicola River serving as a distributional barrier.

Circumscription of genera in the tribe Vernonieae is complex due to overlapping morphological features among genera such as Chrysolaena, Echinocoryne, Lepidaploa, and Lessingianthus. These genera have been segregated from the genus Vernonia s. l., but their classification remains questionable because they lack clear diagnostic characters to contribute to this classification. Several studies have demonstrated the importance of the anatomy of cypselae for classification in Compositae; cypselae provide diagnostic characters for some genera. We studied the anatomy of the cypselae, including pericarp, callus, carpopodium, and pappus of Chrysolaena, Echinocoryne, Lepidaploa, and Lessingianthus, evaluating their potential for clarifying systematic problems in these genera. Our study demonstrated the cypselae features are uniform, and they do not contribute diagnostic characters useful in generic circumscription; however, cypselae anatomical characters do segregate some species. Our data also suggest that Chrysolaena, Echinocoryne, Lepidaploa, and Lessingianthus should be circumscribed in a single genus Lepidaploa.

Siphocampylus nebularis is a new species endemic from the Serra do Mar mountain range in the Paraná state, Brazil. It is morphologically close to S. fulgens due its alternate phyllotaxis, sparsely denticulate leaves, and flowers with reddish corolla tube, differing mainly by the shorter corolla tube, longer calyx lobes, and coriaceous leaves observed in the new species. The new taxon is here described and illustrated. We also propose the inclusion of S. nebularis in the IUCN Red List as an endangered (EN) species due its narrow distribution and the decline of the quality of its habitat.

The genus Daucus is widely distributed worldwide, but with a concentration of diversity in the Mediterranean Region. The D. carota complex presents the greatest taxonomic problems in the genus. We focus on a distinctive phenotypic group of coastal morphotypes of D. carota, strictly confined to the margins to within about 0.5 km of the Mediterranean Sea and the Atlantic Ocean, which we here refer to as coastal morphotypes or D. carota subsp. “gummifer” complex. They are loosely morphologically coherent, sharing a relatively short stature, thick, broad, sometimes highly glossy leaf segments, and usually flat or convex fruiting umbels. We analyzed 288 accessions obtained from genebanks in England, France, and the USA, and an expedition to Spain in 2016, covering the Mediterranean and Atlantic coasts and Balearic Islands, where much of the gummifer complex variation occurs. Our study includes 112 accessions not examined before in this context. Genotyping-by-sequencing identified 29,041 filtered SNPs. Based on high bootstrap support from maximum likelihood and Structure analysis we highlight three main clades. The gummifer morphotypes are intercalated with members of Daucus carota subspecies carota and subspecies maximus in two of these main clades, including a clade containing accessions from Tunisia (also including D. carota subsp. capillifolius) and a clade containing accessions from western Europe (including the British Isles), southern Europe (including the Balearic Islands and the Iberian Peninsula) and Morocco. These results support five independent selections of the gummifer morphotypes in these restricted maritime environments in the Mediterranean and nearby Atlantic coasts. Daucus annuus (=Tornabenea annua) and Daucus tenuissimus (=Tornabenea tenuissima) also fall firmly within D. carota, supporting their classification as morphologically well-defined subspecies of D. carota, which are accepted here under the new combinations Daucus carota subsp. annuus and D. carota subsp. tenuissimus, respectively. Types are indicated for most of treated names, including designation of four lectotypes and three epitypes, which fix their further use.