The phylogenetic position of Cheilanthes brandegeei, a fern endemic to the Baja California Peninsula of Mexico, was investigated using three plastid markers (atpA, rbcL, trnG-R) and comparative morphology. Here we present robust evidence for the recognition of C. brandegeei as a member of the bommeriids, the sister clade to all other cheilanthoid ferns, and evidence that it is sister to all Bommeria species within that clade. Because of its distinctive morphology within the bommeriid clade (pinnate leaf architecture, well-developed pseudoindusium, and narrow, concolorous red-brown rhizome scales), here we propose the new genus Baja to accommodate it. Our results place Baja brandegeei together with other taxa that have a distribution in the Baja California Peninsula and mainland Mexico, rather than with hypothesized congeners in South America and Africa. Morphological characters traditionally used to classify this species as a Cheilanthes (patterns of sporangial distribution, presence of a well-developed pseudoindusium, and fractiferous petioles) are extensively homoplasious across cheilanthoids. We identify three characters that unite the newly expanded bommeriid clade: leaf indument of acicular trichomes, reticulate-cristate perispore morphology, and lateral initiation of the gametophyte meristem.

Two poorly known Malesian vittarioid ferns, Haplopteris angustissima and Monogramma capillaris, are noteworthy for their similar gross morphology. In this study, their systematic relationship was clarified by using molecular phylogenetic analysis which resolved the species in two different clades. Diagnostic morphological characters were further revealed by detailed comparison of almost all the known collections. Although overlaps were found in most of the investigated morphological characters, the venation and silica bodies were found to be useful for species delimitation. Type information, field images, illustrations, and taxonomic notes are provided for both species. A new combination, Haplopteris capillaris, is made and its occurrence in Taiwan as independent gametophytes is confirmed.

A new asplenioid fern species, Asplenium simaoense (Aspleniaceae), found growing on an exposed slope of a limestone mountain in southwestern Yunnan, China, is described and illustrated. A preliminary phylogenetic analysis showed that A. simaoense is strongly supported as sister to A. tenuifolium, whereas A. simaoense is morphologically most similar to A. varians and A. sarelii. However, A. simaoense has rhizome scales entire and petioles (5–)12–20(–25) cm, while A. varians has rhizome scales subentire or fimbriate and petioles (0.5–)2–7(–12) cm and A. sarelii has rhizome scales denticulate and petioles 7–10 cm. Only one population of A. simaoense was found near a road. Its habitat is threatened by road construction and therefore it is recommended to be classified as CR, Critically Endangered, following IUCN red list criteria.

Pinus subsection Cembroides comprises approximately 15 taxa distributed from the southwestern United States to south central Mexico. Despite previous phylogenetic studies based on morphology, nuclear ribosomal DNA, and plastid DNA, we still lack a robust phylogenetic hypothesis and clear delimitation for the closely-related species within the group. We studied the evolutionary relationships within subsection Cembroides and explored incomplete lineage sorting and reticulation using low-copy number nuclear genes. Concatenation and multispecies coalescent phylogenies were inferred from samples representing all taxa from subsection Cembroides and outgroups corresponding to the closely-related subsections Balfourianae, Nelsoniae, Gerardianae, and Krempfianae. The concatenation and coalescence-based trees mainly agreed with one another in recovering Pinus subsection Cembroides as monophyletic and in recovering similar relationships among species as in previous plastid DNA-based studies. Phylogenetic position and admixture analysis suggest that P. californiarum should be treated as a separate species from P. monophylla. Furthermore, our results support recognizing P. fallax as a species rather than as an infraspecific taxon of P. monophylla or P. edulis. The ASTRAL-III tree was consistent with the presence of very high levels of ILS in the group of pinyon pines with small cones. Analyses that account for both incomplete lineage sorting and reticulation identify some unexpected hybridization scenarios that were not reported in the literature.

Phylogenetics work revealed that Aechmea subg. Chevaliera is not a monophyletic group. Seven species previously assigned to the subgenus form a clade with strong statistical support and in sister position to morphologically distinct members of other genera. We present morphological and phylogenetic evidence to segregate these seven species in a new genus named Karawata, which requires the following new combinations: Karawata depressa, Karawata gustavoi, Karawata hostilis, Karawata multiflora, Karawata nigribracteata, Karawata prasinata, and Karawata saxicola. Description of the new genus and its seven species, as well as a key for identification, distribution maps, and illustrations are provided.

Inga kursarii is a new species collected in the terra firme forests of the northwestern Amazon, one of the regions with the highest tree species diversity in the world. According to morphological and phylogenetic analyses, the new species is morphologically similar and sister to Inga gracilifolia Ducke, but it can be distinguished by having 5–6 pairs of caducous leaflets, elliptical leaflets with acute apex and slightly asymmetrical base, spiked inflorescence, subsessile flowers, calyx tube with 4 lobes, tufts of hairs at the apex of calyx lobes, corolla tube with non-reflexed lobes, shorter staminal tubes, and capitate stigma. In addition, analyses of the chemical defensive profile (chemocoding) show that both taxa are chemically different, with I. kursarii having a chemistry based on gallocatechin/epigallocatechin gallates, and I. gracilifolia producing a series of dihydroflavonols. Finally, we present a table with a comparison of diagnostic characters that allows separation of the two species.

Dioecious reproduction, in which unisexual flowers are developed in separate individuals, is an uncommon characteristic that has evolved multiple times independently in angiosperms. Nearly all species in the neotropical genus Clusia are dioecious and most of them are incompletely known because only one sexual morph, either the staminate or the pistillate individual, has been described. Here we explored the variability in chloroplast regions atpF intron, matK, ndhA intron, petL-psbE, rpl16 intron, as well as the nrDNA ITS to evaluate conspecificity between staminate and pistillate individuals within the genus Clusia. Our results indicate that phylogenetic analyses using maximum likelihood and Bayesian inference based on nrDNA ITS data is a suitable approach to assess whether sexual morphs are conspecifics and to estimate species phylogenetic position within the genus. Staminate and pistillate individuals were effectively identified for Clusia araracuarae, C. lundellii, C. stenophylla, and C. uvitana. Distribution maps as well as full morphological descriptions for these species are provided along with comments on their phylogenetic relationships.

A new classification of the predominantly Neotropical tribe Myrteae is proposed to replace Berg's three traditional subtribes, the Myrciinae, Eugeniinae, and Myrtinae. Nine subtribes are here proposed that are supported by molecular and morphological data. In addition to the three traditionally recognized but modified here, subtribe Pimentinae (originally described as Pimentoideae) is reinstated and five new subtribes are proposed: Blepharocalycinae, Decasperminae, Luminae, Pliniinae, and Ugninae. A key to the nine subtribes is followed by descriptions of each, listing genera included, approximate species numbers, general distribution patterns, and notes. The genera Feijoa O. Berg and Temu O. Berg are reinstated. Morphological structures of importance for classification of Myrteae subtribes are illustrated.

With ca. 2500 species, Myrteae is the largest tribe of Myrtaceae and one of the most diverse groups of flowering plants in the tropical Americas. In light of recent systematics adjustments, the present study is a review and provides new insights into floral diversity and evolution in Myrteae. General aspects of floral ontogeny and morphology for the fifty currently accepted genera plus all accepted sections within the large genera Eugenia and Myrcia are summarized based on current morphological data. The discussion provides a broader understanding of the floral diversity across the tribe, highlighting developmental modes, ecological traits, and specializations in reproductive strategies. Hypotheses to be tested in future studies are also presented and discussed.

Arjona is a small genus of hemiparasitic herbs distributed in southern South America. Most species are found in dry open areas in rocky and sandy soils whereas A. pusilla is found in humid places such as wet meadows. Regional treatments recognize five species and two varieties. The species are not clearly defined, and leaf shape and pubescence are the main differentiating taxonomic characters. In this study individuals from four of the five recognized species were examined to reconstruct the evolutionary history of the genus and to test the monophyly of recognized species. Samples covered the range of morphological variability and geographic distribution. The nuclear ribosomal internal transcribed spacer (ITS) regions and two chloroplast spacers (atpB-rbcL and trnL-F) were used to reconstruct the molecular phylogeny of the genus using Bayesian inference and maximum likelihood criteria. The molecular data show that geography better explains phylogenetic groupings than species assignment. This suggests that morphological variation among populations, in the context of the genetic lineages, should be studied in more detail to test the hypothesis that different ecotypes exist in Arjona.

The genus Epithelantha (Cactaceae, Cactoideae, Cacteae) is native to Mexico and the southern USA and includes several uncertain species and ambiguous phylogenetic relationships. We applied multivariate analysis to a set of nine quantitative characters and six qualitative characters and we used Bayesian inference and maximum likelihood to reconstruct the phylogeny of Epithelantha using molecular data from four chloroplast regions (petL-psbE, psbA-trnH, trnL-F, and trnQ-rps16). Eleven taxa were collected in 39 localities where digital images of five individuals were taken. A correlation analysis allowed us to eliminate correlated characters. A discriminant canonical analysis (DCA) for quantitative characters and principal components analyses with mixed data (PCA mix) for quantitative and qualitative characters identified the length of the flower, number of spines, areole length/width ratio, the expansion of the hilar region of the seed, multicellular sculpture, and the relief of the periclinal wall as the most variable characters. The partial least squares-discriminant analysis (PLS-DA) allowed us to recognize nine of eleven taxa. As a complement, the molecular data matrix included 68 substitutions and 12 indels between the four markers. The 39 terminals analyzed were recovered in nine strongly supported clades, confirming the results of multivariate analyses. Epithelantha was recovered as a monophyletic group strongly supported by four substitutions and an indel, with Turbinicarpus being the sister group. Based on our results, we include a taxonomic synthesis of Epithelantha where we recognize ten species, propose two new combinations, designate seven lectotypes, and provide a key for species.

Cyrtandromoea is a genus consisting of about 12 species of perennial caulescent herbs with a distribution in China, India, Myanmar, Thailand, and western Malesia. The genus has previously been associated with either Gesneriaceae or the tribe Mimuleae in Phrymaceae (in former Scrophulariaceae) with morphology in favor of the latter and molecular plastid ndhF data the former. We addressed the placement of this genus by assembling a four gene dataset (matK, ndhF, rps16, and trnL-F) comprising 270 ingroup samples representing 270 species and 51 families of the core asterids, including all families of Lamiales currently recognized. These included 111 species representing 66 genera of Gesneriaceae. We used maximum parsimony, maximum likelihood, and Bayesian inference analyses to reconstruct phylogenies that showed Cyrtandromoea to be placed in Phrymaceae. A fine-scale analysis focusing on Phrymaceae using ITS and trnL-F and 79 samples revealed that Cyrtandromoea is most closely related to a clade of genera in Phrymaceae that included Mimulus s. s. A combination of morphological synapomorphies such as cymose inflorescences, 5-angled toothed calyx, flowers with bilocular ovary with axile placentation with numerous small seeds with endosperm, and loculicidal dehiscing capsule support this placement. Our results strongly support the placement of Cyrtandromoea in Phrymaceae.

Ruellieae is a highly diverse tribe of Acanthaceae in Brazil, and morphological studies of its seeds have revealed important information about the systematics of the tribe. We analyzed the seed morphology of Brazilian species of Ruellieae, using stereoscopic, light, and scanning electron microscopy. The best-sampled genus was Ruellia (53 species), followed by Dyschoriste (seven), and Hygrophila (three); including external groups, a total of 65 species of Ruellieae (68 of Acanthaceae) were sampled. We observed capsular fruits with explosive dehiscence, important for autochory, and discoid seeds covered by hygroscopic and mucilaginous trichomes. The characters most relevant to the taxonomy of the groups were fruit shape, number of ovules, and the distribution, shape, and number of rings on the seed trichomes, the latter two addressed here for the first time. Those characters proved useful for discriminating and characterizing the sampled genera within Ruellieae, and especially the infrageneric clades of Ruellia. Based on the morphological patterns observed, we provide a key for those taxa, and suggest the infrageneric placement of unclassified Ruellia species: R. hypericoides and Ruellia sp. 4 for the clade “Ebracteolati” s. l., Ruellia spp. 2 and 3 for “R. inflata,” Ruellia sp. 1 for “Euruellia” s. s., and R. anamariae for the clade “Blechum.” In a broader context, we corroborate the finding that partial loss of seed trichomes is exclusive to one of the two large lineages of Neotropical Ruellia (lineage II). The hygroscopic and mucilaginous trichomes of Ruellieae seeds play important roles in water retention, germination, protection, and secondary dispersal, and we discuss some aspects of secondary hydrochory and epizoochory on medium- and long-range dispersal of Ruellieae, including transatlantic distances.

Two new species of Rhynchospora section Tenues are described, illustrated, and distinguished from similar species. Rhynchospora chapadensis and Rhynchospora harleyi are both endemic to the campos rupestres (high-elevation rocky meadows) of the Chapada Diamantina, Bahia, Brazil.

A new species of Erythroxylum (Erythroxylum niziae) from west-central Brazil is presented here. Descriptions, illustrations, a map of geographic distribution, and morphological comparisons with morphologically similar species are provided. The novelty differs from its congeners by its subshrub habit 12 to 16 cm in height, firmly chartaceous to coriaceous leaves (8.8–12.7 × 4.3–7.9 cm), and single flowers produced per node along the distal portion of the main branch. A key is provided to differentiate the new species from others occurring in Parque Nacional de Brasília.

During a field expedition to the Serra do Cipó, Minas Gerais state, Brazil, we found a new species of Fritzschia, a genus endemic to campos rupestres from the Espinhaço Range. Fritzschia cordifolia has cordate and succulent leaves with an apical gland, petals with glandular-ciliate margin, campanulate hypanthium, and antesepalous stamens with ventral appendages with deltoid lobes. The presence of seeds with a crested testa is reported here for the first time in Fritzschia. A description and illustration of the new species is provided, as well as its conservation status and its geographical distribution.

Serjania rosalindae and Serjania crucensis (Sapindaceae-Paullinieae), new species from the municipality of La Huacana, Michoacán, Mexico, are described, illustrated, and compared with closely related species. In addition, micromorphological features of the leaves, flowers, and pollen grains are investigated. A treatment of the endemic S. biternata from Guerrero is also included because it is a little-known taxon similar to S. rosalindae whose fruits were previously unknown. All of these taxa share capsules that are chartaceous to almost woody and septifragal, a fruit type otherwise uncommon within Serjania. The distinctive fruit morphology of these species is discussed in relation to other species of Serjania.

A new distylous Waltheria species from Bahia, Brazil, is described and illustrated. Waltheria saundersiae is endemic to the campos rupestres from Bahia and is a shrub with erect to flexuous branches. It can be confused morphologically with Waltheria cinerescens, W. maritima, and W. selloana, however, it is distinguished mainly by the bark ornamentation, leaf arrangement, leaf blade margin, inflorescence position, stylar polymorphism type, calyx size, and staminal tube indument.

Tarenaya longicarpa, commonly known as “mussambê,” is a new species from South America. Iltis previously recognized it as a subspecies of Cleome spinosa Jacq. but never published the name. Molecular phylogenetic studies have confirmed this taxon as a distinct lineage from T. spinosa. In addition, the results of a revision of Tarenaya, now underway, corroborate the separation of T. longicarpa from T. spinosa s. s.

Herein a new species, Varronia xinguana, is described and illustrated. In addition, Varronia polystachya, a species previously known only from Venezuela, is reported for the first time for Brazil. Both species are restricted to the phytogeographic domain of Amazonia, northern Brazil. A distribution map and a conservation assessment are provided. An identification key is also provided for the species of Varronia with spike inflorescence from Northern of Brazil.

Three new species of Justicia (Acanthaceae), Justicia birae, Justicia distichophylla, and Justicia mcdadeana, discovered during the preparation of a taxonomic treatment of Acanthaceae for the “Flora of the cangas of the Serra dos Carajás, Pará, Brazil” are described. Their distribution, habitat data, conservation status, taxonomic comments, and illustrations are provided.

The rediscovery of a carnivorous plant, Utricularia cutleri, in a seasonally flooded coastal plain in the Atlantic Forest domain, is here reported. This species was first described in 1952 with a few collections from that time, and since 1989 was considered a synonym of U. viscosa. Combined macro- and micromorphological evidence using SEM analysis is provided to propose its taxonomic reestablishment. Utricularia cutleri was originally known only from the type collection in Ceará state, and here we report two new records from Mato Grosso and Rio Grande do Norte states, in central-western and northeastern Brazil. Updated morphological description, geographic distribution, and conservation status are provided, as well as comparative discussion with U. viscosa. Moreover, an updated identification key to species of Lentibulariaceae from Rio Grande do Norte is also presented.

The new species Oxylobus coyulensis, currently only known from the Tehuacan-Cuicatlan Valley Biosphere Reserve, located in the states of Oaxaca and Puebla, Mexico, is described. The new taxon can be distinguished from the other species of the genus by leaf shape, leaf trichome diversity, and cypselae surface characteristics. In addition, following a detailed micromorphological study of the species within this genus, it was found that O. juarezensis and O. subglabrus present the same leaf trichome diversity, similar cypselae surface characteristics, and similar macromorphological characters, namely leaf shape and margins, phyllaries, and inflorescence type. As a consequence, it is concluded that O. juarezensis is synonymous with O. subglabrus, as moreover, they are distributed in the same geographical area.