The floristic treatment of Engler and Diels, published in 1901, provides the only infrageneric classification of the pantropical genus Xylopia (Annonaceae). Here we test and extend that classification using molecular and seed morphology characters. Phylogenetic relationships were reconstructed using data from four plastid regions obtained from 44 of the approximately 165 species in the genus, recovering four well-supported major clades. Seed characters were examined for these taxa, and six aril morphologies, three previously undocumented, were distinguished; we also document the presence of a sarcotesta on the seeds of many species. Molecular and seed data support recognition of five sections within the genus; one, Xylopia sect. Rugosperma, is proposed here as new. Our phylogenetic results suggest an African origin for the genus and reveal complex biogeographic patterns, likely facilitated by long-distance dispersal.

Meconopsis is an herbaceous genus native to the high altitude habitats across the Himalaya and adjacent plateau and mountain areas. Attractive Meconopsis flowers have spurred many European botanists to study the taxonomy of the genus resulting in numerous infrageneric classifications, dating from the first taxonomic revision in the late 19th century until the most recent monograph in 2014. All, however, were morphology-based treatments and largely inconsistent with one another. To investigate the incongruence among the previous taxonomic grouping strategies of the species in Meconopsis and settle the controversies, we employed a well-resolved molecular phylogeny built by analyzing four chloroplast markers (trnL-trnF intergenic spacer, matK, ndhF, and rbcL). We found that the evolutionary relationships revealed by our phylogeny disagreed to varying degrees with any infrageneric relationship suggested by previous authors. Therefore, we propose a revised classification based on our phylogenetic topology aswell as themorphological and cytological patterns reflected by the phylogenetic structure. To achieve a practical and approachable system, we have tried to retain as much as possible of phylogenetically meaningful components from previous taxonomies for the genus. As a result, we used the four major clades of our Meconopsis phylogeny as the bases for infrageneric sections (Meconopsis sect. Meconopsis, M. sect. Aculeatae, M. sect. Primulinae, and M. sect. Grandes). A key to the sections is provided, followed by a description and composition of each.

Diversification in Amelanchier tetraploid apomicts differs from that of diploid sexuals and produces groups that are taxonomically difficult. Apomixis facilitates expansion of ecologically successful genotypes into numerous, narrowly distributed, and often minimally distinct microspecies. Residual sexuality in tetraploids creates hybrid swarms and intergradation of taxa. This gene flow is evident in DNA sequences from nuclear and chloroplast regions that record mostly allotetraploid, convoluted histories. Ongoing apomixis in successful tetraploid genotypes fosters their expansion into geographically widespread phenotypic clusters.We delimit such clusters as species and deny species status to microspecies.We demonstrate polyploid complexity and our approach to species delimitation in three taxa of Amelanchier. The tetraploid microspecies A. “rubra” of southeastern Maine, while morphologically distinct, hybridizes with sympatric congeners. Eastern North American A. bartramiana contains diploids and polyploids (tetraploids and a few triploids) that are sometimes morphologically semi-cryptic. We group all ploidy levels in the A. bartramiana agamic complex and recognize as a species the diploid (A. bartramiana). The tetraploid is not given species status because it intergrades extensively with tetraploid congeners, as exemplified by the nothospecies named here, A. ×neglecta. Western North American A. cusickii is tetraploid, mostly distinct morphologically and ecologically, distinct genetically, and merits species status.

Euphorbia polycarpa (Euphorbia subg. Chamaesyce sect. Anisophyllum) is one of the most common species of the Sonoran Desert. It exhibits a wide range of morphological variation and has been considered as a taxonomic complex. Since the late nineteenth century more than seven varieties have been described for the complex, some with very restricted distributions. Because of morphological intergrades present in the complex, there has been much confusion among taxonomists, and it became necessary to clarify the taxonomy of this complex using molecular phylogenetic evidence in addition to morphology alone. In this paper we reconstruct the phylogenetic relationships for the E. polycarpa complex based on molecular information from the psbA-trnH and ITS spacers, using Bayesian inference. Morphology was compared with phylogenetic results, and we also explored geographic patterns of the varieties of the complex, as well as closely related species of Euphorbia sect. Anisophyllum. Taking into account the results obtained, we propose that E. polycarpa is treated as a single, highly variable species. Given the incongruities among morphology, geography, and evolutionary history inferred from molecular data, we do not recognize any of the varieties proposed previously. The phylogeny presented shows three well-supported putative lineages and suggest a complex evolutionary history within E. polycarpa.

Cochlospermaceae (Malvales) is a small family of two genera, Amoreuxia and Cochlospermum. Cochlospermum has a pantropical distribution with species present in Mexico, Central and South America, the West Indies, Africa, India, Southeast Asia, and northern Australia, whereas Amoreuxia has a more restricted distribution in the Americas. Amoreuxia is comprised of four herbaceous species, and Cochlospermum has seven tree species and five that are suffrutescent subshrubs. The two genera also differ in floral symmetry, corolla coloration patterns, and stamen morphology. The goals of this study were to reconstruct the phylogeny of Cochlospermaceae to evaluate the monophyly of the family and its two genera, to resolve interspecific relationships, and to interpret patterns of morphological evolution. In addition, a minor goal was to examine its relationship to sister families, such as Bixaceae, a family in which Cochlospermaceae has been variously placed. Phylogenetic analyses were carried out using DNA sequences of the following markers: nuclear ribosomal ITS and the chloroplast trnG and trnL-F regions. The data support the monophyly of Cochlospermaceae and its distinctiveness from its sister families. While Amoreuxia is supported as monophyletic, Cochlospermum is paraphyletic with two species (C. orinocense and C. tetraporum) consistently placed outside a clade of all remaining Cochlospermum species. Ancestral character state reconstructions of morphology indicate that the tree habit may be ancestral in Cochlospermaceae with a single shift to an herbaceous growth form in Amoreuxia with the suffrutescent growth form having arisen twice within Cochlospermum, once in South America and once in Africa. There has been a single shift in floral morphology from radial symmetry, solid yellow petals, and uniform stamens to bilateral symmetry, two-toned petals, and dimorphic stamens in Amoreuxia. Anthers with one apical pore found in core Cochlospermum species may be a reduction from anthers with two pores, such as those found in Amoreuxia and in C. orinocense and C. tetraporum. Seed shape supports the sister relationships within Cochlospermaceae, particularly within Amoreuxia.

The taxonomic history of Claytonia lanceolata is fraught with confusion. Poor preservation of diagnostic characteristics on museum specimens and incomplete original descriptionsmade from limited reference material have resulted in inadequate characterization of morphological features and geographic distributions, particularly for plants in more xeric areas of California. In this paper, we investigate populations previously thought to belong to C. lanceolata and provide an updated taxonomy for Californian taxa based largely on morphological observations and geographic records. These data are corroborated by evidence of genetic polymorphisms and ecological divergence. Claytonia obovata was synonymized with C. lanceolata in 1966 and remained unrecognized until now because previous treatments misinterpreted morphological variation in C. lanceolata s. s. Claytonia peirsonii is a new combination for a species comprising four subspecies endemic to the Desert Southwest, three of which are new to science. Two new species are described here: Claytonia panamintensis, known in California only from the Panamint Mountains but ranging morewidely across southern Nevada, and Claytonia serpenticola. The latter species shares a similar geographic rangewith C. obovata in the Klamath-Siskiyou region of northern California and southwestern Oregon, and these two occur in close sympatry through much of their respective distributions. We also provide molecular evidence to support retention of the name C. lanceolata for populations in California that do not fall into any of the aforementioned new species or combinations. Taxa accepted in this paper are best distinguished from each other by their habitat (many are apparently edaphic endemics), betalain pigmentation, inflorescence architecture, and morphology of cauline leaves, subterranean stems, and flowers.

An unusual new species of Bidens (Asteraceae) from Brazil is described and its placement within the genus is elucidated by phylogenetic analysis of ITS sequences. The new species, described as Bidens campanulata, is distinct in the genus based on its broadly campanulate corolla limb with long lobes, an extremely reduced involucre (shorter than the flower length), and the absence of awns on the pappus. This study presents a taxonomic treatment of the species of Bidens with discoid capitula endemic to the Brazilian Cerrado, including a key to the species, typification, and information on conservation status.

Fruit anatomical and micromorphological structures from 28 species of Heracleum and three species of Angelica as outgroups were examined under light microscopy to identify characters useful in delimiting clades circumscribed in a previous molecular phylogenetic study. Maximum parsimony analyses of 20 fruit structural characters resulted in a generally poorly resolved strict consensus tree, yet one whose major clades matched those revealed previously. Angelica apaensis and Heracleum xiaojinense are best treated as the single species Angelica apaensis within Angelica s. s. All remaining Heracleum species share a highly lignified hypendocarp and a lignified endocarp, vascular bundles in marginal wings situated in the middle of the wing, and a commissure width the same as the mericarp width. These Heracleum species are recognized in four major clades with the following fruit structural features: (1) Heracleum s. s., having non-septate, clavate dorsal vittae that do not extend to the bottom of the seed; (2) Candicans (Villosa) clade, having marginal wings approximately half thewidth of the fruit and small seeds; (3) Millefolia clade, having narrow marginal wings, long dorsal vittae, large seeds, and rib oil ducts; and (4) Tetrataenium s. s., having prominent dorsal ribs, very wide marginal wings, dorsal and commissural vittae of similar length, 3–4 commissural vittae, and very small seeds.

Chamaecrista tocantinensis, a new species of Chamaecrista sect. Absus subsect. Absus ser. Paniculatae endemic to the Jalapão region in the state of Tocantins, Northern Brazil, is herein described and illustrated. The systematic position, conservation status, flowering and fruiting period, geographical distribution, and morphological relationships of this novel species with C. claussenii var. megacycla, C. lundii, and C. orbiculata var. orbiculata are discussed. A key to all taxa of Chamaecrista hitherto known from the state of Tocantins, including ten new state records, is also provided.

Croton section Geiseleria encompasses 82 species in the Americas, but its center of origin and diversity is in Brazil, where 53 species are distributed especially in areas of Cerrado, in the central part of the country. Taxonomic knowledge of several taxa of Croton section Geiseleria is still scarce, and they are frequently misidentified in Brazilian herbarium collections due to their very similar morphology. During a taxonomic study of this section in the Midwest region of Brazil, a new species was found in the state of Mato Grosso. Croton rhodotrichus is herein described, illustrated, and its relationships with the most morphologically similar species, C. glandulosus and C. hirtus, are discussed. Additionally, distribution, habitat, flowering, fruiting, and conservation status of the new species, as well as a key to identify all the species of Croton section Geiseleria present in the state of Mato Grosso are provided.

The new species Sauvagesia setulosa (Ochnaceae) is described from campo rupestre vegetation of the Espinhaço range, Minas Gerais, Brazil. The corona-like, fused internal staminodes are key to place the new species within Sauvagesia subsect. Vellozianae, a mostly endemic lineage in the Espinhaço range. The combination of bristle-glandular leaves, terminal, umbel-like inflorescences, and flowers with white petals in S. setulosa are unprecedented in any species of Brazilian Sauvagesia. We present a complete description, illustration, distribution map, and a comparative table to morphologically differentiate the new species from the remaining species of Sauvagesia subsect. Vellozianae that bear terminal, umbel-like inflorescences.

The genus Philcoxia (Plantaginaceae) was published less than 20 yr ago, based on three species, and its circumscription has been broadened more recently with the description of two additional species. Here we report the discovery of two new species from the Brazilian Cerrado, bringing the number of currently known species of Philcoxia to seven. We describe and illustrate the new species and provide notes on their taxonomy, morphology, habitat, geographic distribution, phenology, and conservation status, along with a key to all species of the genus. Philcoxia maranhensis is characterized by the non-peltate, cordiform leaves and glandular-pubescent bracts, and is endemic to the Chapada das Mesas, southwestern Maranhão; Philcoxia courensis is characterized by a more developed underground system and is endemic to the Chapada dos Veadeiros, northern Goiás. Both species are assessed as Critically Endangered (CR).

A new species assigned to the genus Pouteria is described and illustrated. Pouteria samborae is morphologically similar to Pouteria glomerata subsp. glomerata and Pouteria macrocarpa, but differs from them by its eucampto-brochidodromous venation pattern, well developed intersecondary veins, tertiary veins with a loose reticulum, and fimbriate inner sepal margins. Environmental, geographic distribution and conservation information for the new species is provided. In addition, a key to the four-lobed corolla species of Pouteria with ciliate margins from the Atlantic rainforest of Brazil is presented.

A new myrmecophytic species, Neonauclea viridiflora, is described from Eastern Samar, Philippines. It bears similarity to N. formicaria, but is easily distinguished by having obovate leaves, smaller flowering heads of 30–35 mm, persistent calyces that are glabrous inside the tube, calyx shafts that are connate at the bases for 0.8–2.5mmor sometimes entirely connate with the adjacent lobe, apical portions of the calyces that are bluntly turbinate but globose to clavate when dry, calyx summits that are bluntly conical but the apex is somewhat flattened when dry, and smaller and slender light green corollas. Comparative illustrations of the calyx lobes, a key to the Philippine myrmecophytic Neonauclea species, and a map for these species' distributions in the Philippines are provided in the study.

The Serra do Cipó, part of the central portion of the Espinhaço Range in Minas Gerais, Southeast Brazil, is known to have been extensively investigated over the past three decades, especially because of the “Flora da Serra do Cipó” project. Nevertheless, some areas have been poorly collected as the efforts were largely concentrated near the roads. Various new species, in several families, have been recently discovered in the campos rupestres of the Serra do Cipó. Here we report the discovery of a new species of Stemodia (Plantaginaceae) from the northwestern slopes. We describe and illustrate the new species based on morphological and micro-morphological evidence, provide information on its taxonomy, habitat, geographical distribution, and conservation status, along with a key to distinguish it from the related species. Stemodia cipoensis is similar to S. harleyi, S. lobata, and S. stellata, being characterized by the presence of long, stiff, curved, eglandular trichomes. It has been assessed as CE (critically endangered) under criteria B1ab(iii) and B2ab(iii), following IUCN guidelines.

A new species, Vernonia occulta (Asteraceae, Vernonieae), from the state of Oaxaca, Mexico is described. The new taxon is distinguished from Vernonia cronquistii, which is also distributed in this region, by fewer florets per head, linear-lanceolate leaves, and different leaf trichomes: the new taxon has uniseriate trichomes with four to six basal cells and one subulate apical cell, while V. cronquistii has lageniform trichomes. We also include an artificial identification key to the Mexican species of the genus Vernonia s. s.