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— Chamaecrista is one of the largest genera of Leguminosae, subfamily Caesalpinioideae. Traditionally, it has been divided into six sections, of which Chamaecrista sect. Absus is the largest, with 31 series. Chamaecrista sect. Absus ser. Setosae comprises nine species. Chamaecrista setosa is the most widely distributed species, comprising four varieties, distinguished by the type and distribution of glandular trichomes, and the leaflet venation. Given the importance of leaflet venation in the delimitation of the taxa, here we performed a study of leaflet architecture of all species of the series and a more detailed morphological study for the Chamaecrista setosa complex. For the study of leaf architecture, 2D images of the leaflets were made using the Faxitron x-ray technique. The morphological studies were based on herbarium specimens. We present the details of the leaflet architecture for the species of Chamaecrista sect. Absus ser. Setosae, and we propose nomenclatural changes for a variety of Chamaecrista setosa and some corrections to typifications. During our studies we also found a new species, Chamaecrista forzzae, which is morphologically similar to Chamaecrista setosa and Chamaecrista multiseta. It is here described and illustrated.

— Plants from Brazilian campos rupestres usually present morphological strategies that allow them to survive in extreme environments. However, in Chamaecrista (Leguminosae, Caesalpinioideae), one of the most diverse genera in the campos rupestres, needle-like leaflets are rare. Reviewing the species that present such leaf morphology, we describe Chamaecrista acicularis, a new species from the Canastra Range, in the southwestern region of the state of Minas Gerais, Brazil. Phylogenetic analyses revealed that C. acicularis is not closely related to other quite similar needle-like leafleted species and that this trait evolved convergently. We also present comments on the phylogenetic relationships of needle-like leafleted species as well as the evolution of the leaflet amplitude, and a detailed description of C. acicularis alongside illustrations, photos, geographical distribution, a key to the needle-like leafleted species and taxonomic notes on similar species. Additionally, we expand the description of Chamaecrista strictifolia and present an informal conservation status for all needle-like leafleted species.

Floras are still important for modern biodiversity studies, as they generate basic information, as well as improve understanding on the diversity of an area. This study aimed to the taxonomic study of the species of Chamaecrista from the Diamantina Plateau in Minas Gerais, Brazil, discussing morphological characteristics of the species and presenting taxonomic novelties. The work was based on the survey of herbaria collections, literature review and field expeditions. Descriptions, an identification key, illustrations of diagnostic features, photographic plates, and commentaries are presented for the 64 species of Chamaecrista from the Diamantina Plateau. Six new species are described, two lectotypifications (C. aurivilla and C. brachystachya) and one neotypification are made (C. echinocarpa), 11 new synonyms and taxonomic changes are proposed for C. astrochiton, C. claussenii, C. echinocarpa, C. exsudans, C. multipennis, and C. orbiculata. Chamaecrista sect. Xerocalyx is treated as a species complex with four taxa although more studies are needed to better understand this group.

A new circumscription of Chamaecrista sect. Chamaecrista ser. Coriaceae is presented based on the results of molecular and morphological analyses. The series is monophyletic upon exclusion of three species that were included within it by Irwin and Barneby. Morphological variation within the series is discussed. Characters previously neglected, such as the detailed morphology of extrafloral nectaries and the position of stamens, are shown to be valuable for taxonomic purposes. The synopsis includes three neotypifications (C. cinerascens, C. mucronata, C. rotundata var. grandistipula), two new synonymizations (C. papillata under C. arrojadoana, and C. rotundata var. grandistipula under C. rotundata var. rotundata), and a new combination (C. arrojadoana). A key for identification of the species, lists of specimens analysed, notes on taxonomy, nomenclature, and geographic distribution of the taxa, as well as illustrations of diagnostic characters are presented. In the new circumscription, the series comprises nineteen species, two of them each further divided into two varieties, to give a total of 21 taxa, distributed mainly in the Brazilian Central Plateau.

A Flora do Brasil 2020 e um projeto coordenado pelo Jardim Botânico do Rio de Janeiro, uma autarquia publica federal vinculada ao Ministerio do Meio Ambiente. Na primeira conferencia da ONU para meio ambiente (conhecida como Rio 92) foi criada a Convencao sobre a Diversidade Biologica (CDB). Esta convencao foi assinado por centenas de paises, inclusive o Brasil, com o claro objetivo de deter a perda da diversidade biologica no planeta. Uma decada depois foi estabelecida dentro da CDB a Estrategia Global para Conservacao de Plantas ou GSPC (sigla em ingles), com metas a serem entregues pelos paises signatarios da CDB a cada decada.O projeto Flora do Brasil 2020 foi idealizado em 2008 para que o Brasil fosse capaz de entregar a meta 1 estabelecida pela GSPC. Conta com a participacao de 979 taxonomistas de 224 instituicoes de 25 paises.

The Global Strategy for Plant Conservation (GSPC) was established by the Conference of Parties in 2002 to decrease the loss of plant diversity, reduce poverty and contribute to sustainable development. To achieve this overarching goal, the GSPC has established a series of targets, one of which is to ensure that plant diversity is well understood, so that it can be effectively conserved and used in a sustainable manner. Brazil hosts more than 46,000 species of plants, algae and fungi, representing one of the most biodiverse countries on Earth, and playing a key role in the GSPC. To meet the GSPC goals of Target 1 and facilitate access to plant diversity, Brazil committed to preparing the List of Species of the Brazilian Flora (2008-2015) and the Brazilian Flora 2020 (2016-present). Managing all the information associated with such great biodiversity has proven to be an extremely challenging task. Here, we synthesize the history of these projects, focusing on the multidisciplinary and collaborative approach adopted to develop and manage the inclusion of all the knowledge generated though digital information systems. We further describe the methods used, challenges faced, and strategies adopted, as well as summarize advances to date and prospects for completing the Brazilian flora in 2020.

Floras são importantes no contexto moderno da biodiversidade, pois além de gerar informações iniciais para diversos estudos, promovem a melhor compreensão da diversidade de uma área. A crescente perda de habitats no bioma Cerrado, que inclui os campos rupestres e é um dos seis “hotspots” mundiais, alerta para a importância de estudos nesse bioma. A família Leguminosae possui alta representatividade nos campos rupestres e Chamaecrista é um de seus gêneros com grande número de espécies, muitas endêmicas. O gênero possui cerca de 330 espécies e duas características marcantes são as anteras pubescentes ao longo das suturas e nectários extraflorais. Apesar da grande importância das Leguminosas, estudos taxonômicos com essa família ainda são incipientes na região do Planalto de Diamantina. O presente trabalho teve como principal objetivo o estudo taxonômico das espécies de Chamaecrista do Planalto de Diamantina, Minas Gerais. O trabalho baseou-se no levantamento das espécies nos principais herbários com coleções do Planalto de Diamantina, em consultas bibliográficas e atividades de campo. Em sua forma final, a dissertação é dividida em dois capítulos, um referente à flora e outro referente à descrição de uma espécie nova. Neles, constam descrições das espécies, chave de identificação, mapas de distribuição geográfica, comentários taxonômicos e ilustrações Floras are important in the modern context of biodiversity, as well as generating initial information to several studies, promoting better understanding of the diversity of an area. The increasing loss of habitats in the Cerrado biome, which includes the rocky fields and is one of six “hotspots” worldwide, highlights the importance of studies in this biome. Leguminosae has high representation in rock fields and Chamaecrista is one of its genera with great number of species, many endemic. The genus has about 330 species and two striking features are the anthers pubescent along the sutures and extrafloral nectaries. Despite the great importance of Leguminosae, taxonomic studies of this family are still incipient in the Diamantina Plateau region. This study aimed to the taxonomic study of the species of Chamaecrista the Diamantina Plateau, Minas Gerais state. The work was based on the survey of the species in the main herbaria with collections from Diamantina Plateau, bibliographic consultations and field activities. In its final form, the dissertation is divided into two chapters, one relating to the flora and the other concerning the description of a new species. There are descriptions of species, key to species, geographic distribution maps, taxonomic comments and illustrations

During a floristic study of Chamaecrista in Diamantina plateau, Minas Gerais state, a new species was discovered. Chamaecrista petiolata is here described, illustrated, and compared to its putative closest relative species, C. catapodia and C. monticola. These species are shrubs, the stem-axis exceeding 1.5 m, and show sessile leaves, whereas C. petiolata is a subshrub up to 40 cm alt., with short petiolate leaves. The new species belongs to subsection Absus, which is characterized by glandular trichomes and lack of extrafloral nectaries.