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A taxonomic revision of the species currently circumscribed in Tarenaya Raf. (Cleomaceae) is presented here. Tarenaya comprises 38 species distributed from Mexico to Argentina (except for Chile) and the West Indies, and with one species disjunct in Central Africa. We present a new combination, 14 lectotypifications, and two neotypifications, and describe a new species endemic to Espírito Santo, Brazil. We provide a detailed description of the genus, an identification key to the species, and, for each species, we provide descriptions, geographic distribution data, and preferred habitats, diagnostic features, morphological comments, extinction risk assessment, photographs, illustrations, and distribution maps.

Floral colors and odors are evolutionary strategies used by plants to attract pollinating animals and may be absent in mostly anemophilous groups, such as Cyperaceae. However, considering that insects are floral visitors of some Rhynchospora Vahl species, the objective of this study was to characterize the floral traits and pollination systems within this genus. We analyzed 16 Rhynchospora species with regard to flower morphology, colors of floral structures, floral scents, pollen vectors, and pollination systems. We verified factors that can favor abiotic or biotic pollination in a continuum of floral traits in Rhynchospora. The flower morphology of R. dissitispicula T. Koyama, with inconspicuous brown spikelets in open panicles, is interpreted as a complete adaptation to anemophily. Conspicuous floral traits in Rhynchospora were distinguished from the background by bees. Some species also emit floral volatiles, and we made the first record of floral scent chemistry within the genus. Most of the compounds emitted by these species are known as attractants to many floral-visiting insects. Bees, beetles, and flies visited species with conspicuous floral traits and contributed to fruit set. The investigated floral traits form a continuum across the different pollination systems in Rhynchospora, from anemophilous to ambophilous and then to entomophilous representatives.

We present a taxonomic study of the Myrtaceae family in a fragmented landscape known as Amazonian Maranhão. The botanical collections were made from August 2019 to February 2020. Other collections were studied in loco at HST, IAN, IPA, MAR, MG, NY, PEUFR, and SLUI, and others online at virtual herbaria. Myrtaceae are represented in Amazonian Maranhão by 37 species. The most diverse genera are Myrcia with 16 species and Eugenia with 15 species, followed by Myrciaria and Psidium with two species each, and Campomanesia and Calycolpus with one each. Some of the species are cited here from Maranhão for the first time, and have their geographic distribution extended, including Eugenia dittocrepis, E. lambertiana, E. patens, E. patrisii, Myrcia bracteata, M. eximia, and Psidium acutangulum. A taxonomic treatment for the family in the region, with an identification key to the species, detailed descriptions and taxonomic comments for each species is presented.

Background and Aims With the advance of high-throughput sequencing, reduced-representation methods such as target capture sequencing (TCS) emerged as cost-efficient ways of gathering genomic information, particularly from coding regions. As the off-target reads from such sequencing are expected to be similar to genome skimming (GS), we assessed the quality of repeat characterization in plant genomes using these data. Methods Repeat composition obtained from TCS datasets of five Rhynchospora (Cyperaceae) species were compared with GS data from the same taxa. In addition, a FISH probe was designed based on the most abundant satellite found in the TCS dataset of Rhynchospora cephalotes. Finally, repeat-based phylogenies of the five Rhynchospora species were constructed based on the GS and TCS datasets and the topologies were compared with a gene-alignment-based phylogenetic tree. Key Results All the major repetitive DNA families were identified in TCS, including repeats that showed abundances as low as 0.01 % in the GS data. Rank correlations between GS and TCS repeat abundances were moderately high (r = 0.58–0.85), increasing after filtering out the targeted loci from the raw TCS reads (r = 0.66–0.92). Repeat data obtained by TCS were also reliable in developing a cytogenetic probe of a new variant of the holocentromeric satellite Tyba. Repeat-based phylogenies from TCS data were congruent with those obtained from GS data and the gene-alignment tree. Conclusions Our results show that off-target TCS reads can be recycled to identify repeats for cyto- and phylogenomic investigations. Given the growing availability of TCS reads, driven by global phylogenomic projects, our strategy represents a way to recycle genomic data and contribute to a better characterization of plant biodiversity.

The recovery of tree species composition after disturbance depends on dispersal either from nearby forests or from surviving individuals within the disturbed area. Understanding the influence of proximity to mature forests on species composition of regenerating secondary forests can help in predicting the trajectory of recovery from anthropogenic disturbances. Using forest inventory data from a chronosequence of regenerating secondary forests in the Atlantic Forest of southern Bahia, whereby transects were arranged from the edge of mature forest 100 m into the regenerating area, we calculated community weighted means (CWMs) for traits and the natural distribution ranges of species. We used Generalized Linear Mixed Models to investigate whether site characteristics such as forest age, distance from mature forest edge, soil chemical and physical properties, and canopy openness influence traits and natural distribution of regenerating secondary forest tree species. Results show that species traits were associated with regenerating forest age while the proportion of endemic and widespread species was associated with distance from mature forest and regenerating forest age. Irrespective of distance from mature forest, regenerating secondary forests recruit species with heavy and recalcitrant seeds, but this increased with regenerating forest age. Our results contribute to understanding the effects of forest fragmentation and in restoring forests after deforestation.

Background and Aims While variation in genome size and chromosome numbers and their consequences are often investigated in plants, the biological relevance of variation in chromosome size remains poorly known. Here, we examine genome and mean chromosome size in the cyperid clade (families Cyperaceae, Juncaceae and Thurniaceae), which is the largest vascular plant lineage with predominantly holocentric chromosomes. Methods We measured genome size in 436 species of cyperids using flow cytometry, and augment these data with previously published datasets. We then separately compared genome and mean chromosome sizes (2C/2n) amongst the major lineages of cyperids and analysed how these two genomic traits are associated with various environmental factors using phylogenetically informed methods. Key Results We show that cyperids have the smallest mean chromosome sizes recorded in seed plants, with a large divergence between the smallest and largest values. We found that cyperid species with smaller chromosomes have larger geographical distributions and that there is a strong inverse association between mean chromosome size and number across this lineage. Conclusions The distinct patterns in genome size and mean chromosome size across the cyperids might be explained by holokinetic drive. The numerous small chromosomes might function to increase genetic diversity in this lineage where crossovers are limited during meiosis.

While studying the collections of Cryptangieae (Cyperaceae) at the New York Botanical Garden, we found specimens of two undescribed species, which based on their achene morphology are assigned to the genus Cephalocarpus. We name and describe these two new species, C. insolitus and C. neblinensis, from the Guayana Highland of northern South America. Both species have three fimbriate hipoginium scales on opposite sides of the fruit and a constriction zone between the main body and the beak of the achene, as in other species of Cephalocarpus. We also provide illustrations, distribution maps and comments about the taxonomy and distribution for each species.

Cryptangieae is a monophyletic tribe, as asserted in a recent molecular hypothesis, but there are questions about the circumscription and relationships of its genera. We enlarged the sampling of the tribe diversity, including about 80% of known species, and provide new analyses using single and combined matrices from two chloroplast (rbcL and trnL-F) and three nuclear ribosomal (ITS, ETS and 5S-NTS) regions with Bayesian Inference to clarify these questions. We also performed character reconstruction analyses with diagnostic morphological characters, including some traditionally applied in Cryptangieae taxonomy, using parsimony methods. The molecular analyses show Lagenocarpus in the current circumscription as polyphyletic, and the need to merge Cephalocarpus and Everardia to avoid paraphyletic genera. We propose an updated circumscription following the phylogeny, including a new name to a group at generic level (Krenakia); and discuss the phylogenetic significance of the morphological characters in Cryptangieae taxonomy. Though the relationship among some genera still needs more research, the genera we propose are strongly supported clades with clear morphological synapomorphies. Additionally, we provide an identification key, a brief description of genera and a list of accepted species including the required new combinations.

Rhynchospora is one of the most species-rich genera of Cyperaceae, comprising c. 400 species in 28 sections. Rhyncospora section Tenues is one of the largest sections and one of the most problematic. Because it is morphologically similar to sections Laevinuces, Luzuliformes and Spermodontes, the characters traditionally used to distinguish section Tenues cannot be reliably used to place species into one of these four sections. These four sections are included in the Psilocarya group of Rhynchospora subgenus Rhynchospora with sections Psilocarya and Dichromena. Previous molecular studies of Rhynchospora indicate that species of the Psilocarya group form a clade and are sister to at least some species of the sections being studied here. Since only 11 of the estimated 41 species in these four sections were included in earlier phylogenetic studies, the relationships among these sections remain unclear. To elucidate these relationships, we conducted a molecular phylogenetic analysis for Rhynchospora, based on plastid trnL-F and nuclear ETS and ITS markers, emphasizing species in these four sections. Results show that sections Laevinuces, Spermodontes and Tenues are individually not monophyletic but, grouped together, form a well-supported clade, Rhynchospora section Tenues s.l. Rhynchospora section Luzuliformes is monophyletic but is not a sister clade of section Tenues.

During the preparation of a taxonomic revision of Rhynchospora sect. Longirostres, we found several scientific names that needed to be lectotypified or neotypified. In addition, Rhynchospora amazonica subsp. guianensis is being recognized at the level of species and requires a new name, Rhynchospora rionegrensis. This species is described and illustrated and differs from R. amazonica by its lateral and terminal, generally turbinate inflorescences, brown spikelet scales, loose fascicles, and longer stylopodium. Lectotypes are chosen for Calyptrostylis longirostris (the basionym of R. rionegrensis), R. amazonica, and R. macrostachya, and a neotype chosen for R. stenocarpa.

Recent molecular phylogenies have demonstrated that Pleurostachys (Cyperaceae) should be recognized as a section within Rhynchospora. Here all accepted species of Pleurostachys are transferred to Rhynchospora sect. Pleurostachys, five new combinations are made, and one new name provided. Rhynchospora austrobahiensis and R. contraligularis are described as new species endemic to the Atlantic forest of southern Bahia, Brazil. They are distinct from all other species of sect. Pleurostachys by having spikelets that are never clustered and basal leaves over 1 cm wide. The summit of the inner band of the leaf sheath on R. austrobahiensis is concave to triangular while that of R. contraligularis is arched with a distinct, chartaceous contraligule. Both species are illustrated and compared to other species of Rhynchospora sect. Pleurostachys.

Background and Aims Eriocaulaceae exhibit a great variety of floral traits associated with insect (e.g. nectariferous structures) and wind pollination (unisexual flowers, exposed sexual organs and small pollen grains), as well as the ‘selfing syndrome’ (small flowers, short distance between stigma and anthers, and temporal overlap of male and female phases). Paepalanthus bifidus, P. subtilis and P. tortilis are related species that differ in form, size and colour of floral structures. We aimed to investigate the pollination and reproductive biology of these three species. Methods We analysed the floral biology, floral visitors, pollinator behaviour, and the contribution of insects, wind and spontaneous geitonogamy to fruit set. We also evaluated the floral colour and scent of the species. Colour reflectance of capitula of each species was measured and plotted in models of insect vision. Floral scent samples were extracted and the compounds were compared to vegetative scent samples. Key Results In all species, the staminate and pistillate flowers are arranged in alternating cycles with a temporal overlap between these phases. Ants were the most frequent floral visitors and were effective pollinators in P. bifidus and P. tortilis, while flies were occasional pollinators in P. tortilis. Floral visitors were not observed in P. subtilis. In all species, fruits were produced by spontaneous geitonogamy, with no evidence of wind pollination. According to the models of insect vision, the colours of the capitula of P. bifidus and P. subtilis are the most inconspicuous for ants and flies. We found no difference between the emission of volatiles of inflorescences and vegetative structures. Conclusions This study suggests that ant pollination might be more widespread in Eriocaulaceae than currently assumed. Furthermore, for small monocarpic plants, mixed mating strategies are most favourable, by ensuring reproduction either by outcrossing when pollinators are abundant or by spontaneous geitonogamy when pollinations are scarce/absent.

—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.

—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.

Tropical forests are converted at an alarming rate for agricultural use and pastureland, but also regrow naturally through secondary succession. For successful forest restoration, it is essential to understand the mechanisms of secondary succession. These mechanisms may vary across forest types, but analyses across broad spatial scales are lacking. Here, we analyse forest recovery using 1,403 plots that differ in age since agricultural abandonment from 50 sites across the Neotropics. We analyse changes in community composition using species-specific stem wood density (WD), which is a key trait for plant growth, survival and forest carbon storage. In wet forest, succession proceeds from low towards high community WD (acquisitive towards conservative trait values), in line with standard successional theory. However, in dry forest, succession proceeds from high towards low community WD (conservative towards acquisitive trait values), probably because high WD reflects drought tolerance in harsh early successional environments. Dry season intensity drives WD recovery by influencing the start and trajectory of succession, resulting in convergence of the community WD over time as vegetation cover builds up. These ecological insights can be used to improve species selection for reforestation. Reforestation species selected to establish a first protective canopy layer should, among other criteria, ideally have a similar WD to the early successional communities that dominate under the prevailing macroclimatic conditions.

As recognized traditionally and until recently, Simaba ferruginea A.St.-Hil. sensu Engler was a polymorphic taxon with a disjunct distribution on dry formations of central and northeastern Brazil, and the northernmost region of Colombia and adjacent Venezuela. A detailed morphological survey of this complex based on fieldwork and herbarium specimens recovered three closely related but clearly distinct groups of plants, including a new species endemic to La Guajira, Colombia. A recentmolecular phylogenetic study strongly corroborates the relatedness of the three groups and places them in the genus Homalolepis. Each group, herein treated as a distinct species, has distinctive morphological features, specific habitat preferences, and is allopatric from the other groups. Homalolepis ferruginea sensu strictu is endemic to the cerrado formation on the Brazilian Central Plateau. Homalolepis bahiensis, reinstated here as a distinct species, occurs along the sandy coastal plains in northeastern Brazil. Homalolepis guajirensis is described as a new species, and it is endemic to La Guajira peninsula in Colombia. We present a table and a key to distinguish the three species, full descriptions, geographical and ecological data, and assess the conservation status for each, following IUCN criteria.

A new species of Rhynchospora section Tenues, from western Bahia, Brazil, is described, illustrated, and compared to related species.

Although Cyperaceae are considered anemophilous, some species exhibit features that are attractive to pollinators, such as the white UV-reflecting involucral bracts of Rhynchospora ciliata. But how effective are these conspicuous adaptations? To address this question, we tested the hypothesis that species such as R. ciliata are visited by greater numbers of pollinating insects than similar species with green involucral bracts, such as R. pubera. We compared the floral biology of both species and the number of visits to sympatric populations of each species, associating them with the availability of pollen and the pollination system. We verified that species with white involucral bracts are preferred, because there were more visits to R. ciliata in the first 2 h the flowers were open. The peak visitation in R. pubera was 2 h after the flowers opened, when the pollen of R. ciliata was exhausted. Although the involucral bracts of R. pubera are green, the spikelet scales and anthers are white and reflect ultraviolet light. Overall, flowers of R. pubera exhibit fewer white or reflective surfaces and are probably less conspicuous to a bee than those of R. ciliata. It is possible that R. pubera is a second option for visitors after the first 2 h of anthesis. The two different peaks in visitation minimize interspecific competition for pollinators, suggesting that R. ciliata and R. pubera together could attract more generalist pollinators and, instead of competing, facilitate the pollination of both species. Although R. pubera is autogamous and self-compatible, both wind and insects are important to its reproductive success.

Tropical secondary forests recover quickly (decades) in tree species richness but slowly (centuries) in species composition., Old-growth tropical forests harbor an immense diversity of tree species but are rapidly being cleared, while secondary forests that regrow on abandoned agricultural lands increase in extent. We assess how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics. Secondary forests recover remarkably fast in species richness but slowly in species composition. Secondary forests take a median time of five decades to recover the species richness of old-growth forest (80% recovery after 20 years) based on rarefaction analysis. Full recovery of species composition takes centuries (only 34% recovery after 20 years). A dual strategy that maintains both old-growth forests and species-rich secondary forests is therefore crucial for biodiversity conservation in human-modified tropical landscapes.

Seed arrival is a limiting factor for the regeneration of diverse tropical forests and may be an important mechanism that drives patterns of tree species' distribution. Here we quantify spatial and seasonal variation in seed rain of secondary forests in southern Bahia, Brazil. We also examine whether secondary forest age enhances seed dispersal and whether seed rain density and diversity in secondary forests decay with distance from mature forest. Across a chronosequence of 15 pairs of mature and secondary forests, 105 seed traps were installed and monitored for one year. We tested the effects of secondary forest age, distance from mature forest, and seasonality on monthly seed rain density, diversity, seed dispersal mode, and diaspore size. We found that secondary forest age had strong, positive effects on the diversity of seed rain, which was generally higher during the wet season. Moreover, contrasting patterns among diversity indices revealed that seeds of rare species occurred more often in 40 yr old secondary forests and mature forests. While the proportion of biotically and abiotically dispersed seeds did not change significantly with distance from mature forest across all forest age classes, we found that biotically dispersed seeds contributed disproportionately more to seed rain diversity. Our results emphasize the importance of biotic dispersal to enhance diversity during secondary succession and suggest that changes in secondary forest structure have the potential to enhance the diversity of tropical secondary forests, principally by increasing dispersal of rare species. peerReviewed

Aim Using a comprehensive floristic database (2616 species, 36,004 occurrence records from 128 unique localities), we model species turnover along the central region of the Atlantic Forest hotspot to (1) test whether local rivers, particularly the Rio Doce, are associated with marked biogeographical breaks, and (2) investigate how regional compositional changes correlate with geo-climatic variables. Location The central region of the Atlantic Forest in eastern Brazil (12°–22° S latitude). Methods We combine occurrence and geo-climatic data in a generalized dissimilarity model, obtaining a continuous prediction of species turnover across space and identifying 12 significant geo-climatic predictors of community composition. We use a two-step cluster analysis to classify the turnover map into major floristic regions based on the natural subgroups observed. We further divide each major floristic region into smaller sub-regions based on natural subgroups statistically identified by the two-step cluster analyses. Results High levels of turnover in species composition occurred around latitudes 18°–19° S, c. 50–100 km north of the Rio Doce, and concurred with shifts in availability of both humidity and energy. We identified three major floristic regions in the central region of the Atlantic Forest, which we called Bahia Interior Forests, Bahia Coastal Forests, and the Krenak-Waitaka Forests – each of them divided into two to four subregions. Main conclusions Our results suggest that local climatic conditions, not riverine barriers, drive biogeographical shifts in this region – a finding that supports studies of current and historical determinants of the composition of the Atlantic Forest biota. Floristic composition at higher elevations (> 600 m) is clearly distinct from those in lower elevations, likely as a result of physiological constraints imposed by cooler climates in the former. Floristic regions here identified from observed communities substantially improve the maps currently employed for conservation planning in a shrinking hotspot.

In this paper we describe and illustrate a new species of Simaba from the sandy coastal plains in northeastern Brazil, and discuss the controversial limits of the three sections proposed in the genus by Englerian classification. Simaba arenaria has a restricted distribution: it is known only from two small, somewhat disturbed areas, in restinga vegetation of Bahia and Sergipe states. The evaluation of its threatened status indicates that it is an endangered taxon, according to the IUCN Red List categories and criteria. We also provide novel data on the seedling of this species.

As part of The New York Botanical Garden’s 125th anniversary, a summary of floristic research by NYBG staff is presented. The first 50 years of the Garden were extremely productive and resulted in floras covering most of the United States and Canada. The focus of research at the Garden shifted to the Neotropics and diversified, especially in northern South America and Brazil, and continues to thrive.

Background: Understanding floristic and geographic patterns in one of the most biodiverse regions in the world – the Atlantic forest of eastern Bahia, Brazil – can identify the drivers of diversity in tropical forests and provide useful information for biological conservation.Aims: To understand the role of both climate and geographical location on variation in tree species composition in a region characterised by an abrupt transition from wet forests to semi-arid thorn-woodlands. To test whether a regional classification of forests according to elevation belts and leaf flush pattern is consistent with floristic composition.Methods: We submitted 14,094 tree species occurrence records and 31 geo-climatic variables prepared for 57 sites in eastern Bahia, Brazil, to multivariate and regression analyses and variance partitioning.Results: Climate and space were both significantly (P ≤ 0.05) contributing to explaining floristic variations. Actual evapotranspiration, duration of water deficit, and minimum temper...

One of the greatest challenges in achieving the goals of the World Flora Online (WFO) will be to make available the huge amount of botanical information that is not yet available digitally. The New York Botanical Garden is using the Flora Neotropica monograph series as a model for digitization. We describe our efforts at digitizing Flora Neotropica monographs and why digitization of hardcopy descriptions must be a priority for the WFO project. Resumo Um dos maiores desafios para alcançar as metas do projeto World Flora Online (WFO), será a disponibilizar a enorme quantidade de informações botânicas que ainda não estão disponíveis digitalmente. O New York Botanical Garden está utilizando a série de monografias da Flora Neotropica como um modelo para a digitalização. Nós aqui descrevemos nossos esforços na digitalização das monografias da Flora Neotropica e porque a digitalização das descrições impressas deve ser uma prioridade para o projeto WFO.

Rhynchospora seccoi, a new species of Rhynchospora sect. Tenues (Cyperaceae) is herein described and illustrated. This new species from Serra dos Carajás (Pará State, Brazil) is morphologically similar to R. tenuis and R. riparia, but differs by being annual and having often cauline leaves, a synflorescence comprising 1 terminal and 2–3 axillary paniculodia, a nutlet with a rounded apex, a nutlet surface with 8–10(12) transverse ridges of vertically oriented linear cells, and a persistent style-base that is brown, shallowly triangular, and shortly bilobed at the base, with the lobes not extending along the shoulders of nutlet.

The taxonomic identity of Rhynchospora panduranganii and R. corymbosa (Cyperaceae) is resolved based on a detailed study of both herbarium specimens and living collections. We provide distinguishing characters of both species, along with photographs for easy identification.

Rhynchospora Vahl (1805:229) is the richest genus of Cyperaceae in southern Brazil (66 spp., Flora do Brasil 2020). Most species grow in open areas such as meadows and grasslands but some occur in forests or along forest edges. As part of a taxonomic and phylogenetic study of the related sections Luzuliformes Kük. (1950:183) and Tenues Kük. (1950:186), we revised specimens in the herbaria of the New York Botanical Garden (NY) and the United States National Herbarium (US). We found specimens of two new species from the states of Santa Catarina and Paraná in southern Brazil and sought additional specimens of these species in the principal herbaria of southern Brazil (FLOR, HBR, ICN, MBM). These two species clearly belong to sections Tenues and Luzuliformes, which were last revised by Rocha and Luceño (2002) and Silva Filho et al. (2017). Both species are here described, compared to related species (Table 1), and illustrated (Figures 1 and 2).

Homalolepis Turcz. is a neotropical, monophyletic genus, recently reestablished as a segregate from Simaba Aubl., based on molecular and morphological grounds. As here defined, Homalolepis comprises 28 species, mainly distributed in tropical South America, with one species extending to Central America. Most species occur within the Cerrado and Atlantic forest domains in Brazil and only a few species occur in the Caatinga and Amazonian domains or in other countries. Most of the species are narrow endemics, and two (H. suaveolens and H. maiana) are presumably extinct. The present revision treatment is primarily based on the examination of about 1300 specimens from 58 herbaria. Natural populations of 20 species were also studied. Extensive field work improved the representativeness of collections of several species which were poorly known until now, and it was critical for achieving accurate species circumscriptions, especially for some species complexes present in the genus. Twenty-three species were transferred from Simaba to Homalolepis, seven names lectotypified, an epitype designated, seven new species described, and one reestablished. The infrageneric classification is reevaluated, with an updated morphological circumscription of two traditional sections. This revision provides the taxonomic data on nomenclatural types, including synonymies, morphological descriptions, etymology of species names, common names and uses, illustrations and photos, and brief discussions on phenology, taxonomy and nomenclature. Distribution maps are provided for each species, along with biogeographical and ecological comments.

We describe and illustrate two new species of Homalolepis Turcz. (Simaroubaceae), a genus recently reinstated based on molecular evidence indicating that Simaba Aubl. as currently circumscribed is not monophyletic. Both species are dwarf, geoxylic subshrubs with restricted distribution in the Brazilian savanna (cerrado). Homalolepis planaltina is so far known from a single population, in highland fields of southeastern Minas Gerais state, and belongs to H. sect. Grandiflorae. The few known populations of H. pumila are restricted to the Emas National Park in the state of Goias and belong to H. sect. Homalolepis . We present live pictures of plants of both species in their habitats, as well as drawings of diagnostic features, an identification key to the geoxylic species, detailed descriptions, distribution maps, data on geography and ecology, the conservation status, and comments on morphology and closely related taxa. These two new taxa increase the total diversity of the genus to 28 accepted species.

RESUMO Realizou-se um estudo da flora e da estrutura da vegetacao no Cariri Paraibano com o objetivo de subsidiar estrategias para conservacao e uso sustentavel da caatinga na regiao. No levantamento floristico considerouse toda a area do Cariri, mas para os estudos de estrutura foram selecionadas duas localidades em diferentes estadios de conservacao: a RPPN Fazenda Almas (7°2815”S, 36°53’51”W), Cariri Ocidental, area mais preservada, e a Estacao Experimental de Sao Joao do Cariri (7o23’48”S e 36o31’55”W), Cariri Oriental, com vegetacao bastante alterada. No levantamento floristico foram observadas 396 especies, sendo a familia Leguminosae a mais diversa. Em Sao Joao do Cariri foram observadas 26 especies arboreo-arbustivas e a dominância de Caesalpinia pyramidalis, Croton sonderianus, Combretum leprosum e Jatropha mollissima. Na Fazenda Almas registraram-se 67 especies arboreo-arbustivas, destacando-se tambem Croton sonderianus e Caesalpinia pyramidalis e ainda Manihot catingae. A baixa diversidade floristica encontrada na EE Sao Joao do Cariri refletiu-se em todos os parâmetros estruturais de vegetacao analisados indicando a degradacao da vegetacao local, que ha anos e utilizada para pastoreio de caprinos. A diversidade na RPPN Fazenda Almas foi bastante superior a observada em Sao Joao do Cariri e em outras areas de caatinga na Paraiba. Palavras-chave: Caatinga, diversidade, estrutura, Paraiba

Since the Monocots II meeting in 1998, significant new data have been published that enhance our systematic knowledge of Cyperaceae. Phylogenetic studies in the family have also progressed steadily. For this study, a parsimony analysis was carried out using all rbcL sequences currently available for Cyperaceae, including data for two new genera. One of the four subfamilies (Caricoideae) and seven of the 14 tribes (Bisboeckelereae, Cariceae, Cryptangieae, Dulichieae, Eleocharideae, Sclerieae, Trilepideae) are monophyletic. Subfamily Mapanioideae and tribe Chrysitricheae are monophyletic if, as the evidence suggests, Hellmuthia is considered a member of Cypereae. Some other features of our analysis include: well-supported Trilepideae and Sclerieae-Bisboeckelereae clades; a possible close relationship between Cryptangieae and Schoeneae; polyphyletic tribes Schoeneae and Scirpeae; the occurrence of Cariceae within the Dulichieae-Scirpeae clade, and a strongly supported clade, representing Cyperus and allied genera in Cypereae, sister to a poorly supported Ficinia-Hellmuthia-Isolepis-Scirpoides clade. Such patterns are consistent with other studies based on DNA sequence data. One outcome may be that only two subfamilies, Mapanioideae and Cyperoideae, are recognized. Much further work is needed, with efforts carefully coordinated among researchers. The work should focus on obtaining morphological and molecular data for all genera in the family.

(Hypolytrum (Cyperaceae): taxonomic and nomenclatural notes, geographical distribution and conservation status of Neotropical species.) Hypolytrum (Mapanioideae) is a medium-size and Pantropical genus of Cyperaceae, closely related to Mapania, Principina, and Scirpodendron. In the Neotropics, it is found from southern Mexico to southern Brazil where it grows in the Atlantic and Amazon Forests and Cerrado vegetation. Most of the species are found in the humid and shady understory of forested habitats. Twenty-nine species are confirmed, nine of which are considered narrow-endemics and one is poorly known. Twelve species are classified under the conservation status of Critically Endangered or Vulnerable. A total of 130 types (holo- types, isotypes, lectotypes and isolectotypes) and 42 photos of types were checked and confirmed, and 22 synonyms were verified and accepted. Information about geographic distribution including new occurrences, habitat and diagnostic characters are also provided.

Pleurostachys Brongn. is a Neotropical genus of Cyperaceae closely related to Rhynchospora Vahl. It is found in the Atlantic and Amazon Forests from northern South America to southern Brazil and most of the species grow in the humid and shady understory. Fourteen species are confirmed, 11 of them are endemic to the Brazilian Atlantic Forest and six are considered under the conservation status of Vulnerable. New synonyms and lectotypes are also indicated.

Hypolytrum Rich. (subfamilia Mapanioideae) tem distribuicao pantropical e esta representado por 16-21 especies na regiao Neotropical, das quais grande parte ocorre no Brasil habitando diferentes ecossistemas. Sao apresentados dados de anatomia foliar com maior relevância taxonomica para 10 especies do genero. Entre eles, destacam-se: formato da folha em seccao transversal; presenca de grânulos, provavelmente de silica, em celulas epidermicas; aspectos da cuticula, da hipoderme e do parenquima lacunoso; numero de camadas e origem (hipodermica e epidermica) das celulas buliformes; presenca de celulas epidermicas papilosas; e ocorrencia de parenquima radiado nos feixes menores. Os estudos de anatomia foliar mostram-se relevantes na delimitacao generica e especifica, porem nao apoiam as seccoes taxonomicas estabelecidas.

Fil: Do Nascimento Prata, Ana Paula. Universidade Federal de Alagoas. Centro de Ciências Agrária; Brazil. Fil: López, María Gabriela. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina. Fil: Thomas, William Wayt. The New York Botanical Garden; Estados Unidos. During the revision of the genus Bulbostylis for Brazil four new species were found, which are proposed here. Bulbosty lis amazonica, B. decidua, B. minensis and B. wanderleyana are fully described, illustrated, and compared to other South American species Quatro novas espécies de Bulbostylis foram descobertas durante a revisão deste gênero para o Brasil e estão sendo propostas neste trabalho: Bulbostylis amazonica, B. decidua, B. minensis e B. wanderleyana. Todas as espécies são descritas e ilustra das. Além disso, comparação com outras espécies sul americanas é feita.