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ResumoWinteraceae apresenta cinco gêneros, dos quais apenas Drimys ocorre na região neotropical. A taxonomia das espécies ocorrentes no Brasil ainda é controversa e dependendo do autor, são aceitas de uma a três espécies. O presente trabalho apresenta o estudo taxonômico de Winteraceae no Rio Grande do Sul, e visa esclarecer acerca das espécies da família no estado. Foram feitas revisões de herbários nacionais e internacionais, além de coletas em diversos pontos do estado para o levantamento de dados para o tratamento taxonômico e a análise morfométrica (ANOVA). Com base nas análises morfométricas, dados fenológicos e morfológicos, aceitamos a ocorrência de duas espécies no Rio Grande do Sul: Drimys angustifolia e D. brasiliensis. É fornecida uma chave de identificação, descrições, comentários, fenologia e ilustrações de ambos os táxons. Palavras-chave: Canellales, Drimys, elemento austro-antártico, Magnoliidae, morfometria. AbstractWinteraceae presents five genera, of which only Drimys occurring in the Neotropics. The taxonomy of the Brazilian species is still controversial, and depending on the author, one to three species is accepted. This paper presents the taxonomic study of Winteraceae in the state of Rio Grande do Sul, and aims to elucidate the Winteraceae species for the region. Revision of national and international herbaria, and collections in several places of the state were made in order to gather data for the taxonomic treatment and the morphometrics analysis (ANOVA). Based on the morphometric analyses, phenological and morphological data, two species are accepted for Rio Grande do Sul: Drimys angustifolia and D. brasiliensis. We provide an identification key, descriptions, commentaries, phenology and illustrations for both taxa.

Laminae of Adiantum raddianum Presl., a fern belonging to the family Pteridaceae, are characterised by the presence of epidermal fibre-like cells under the vascular bundles. These cells were thought to contain silica bodies, but their thickened walls leave no space for intracellular silica suggesting it may actually be deposited within their walls. Using advanced electron microscopy in conjunction with energy dispersive X-ray microanalysis we showed the presence of silica in the cell walls of the fibre-like idioblasts. However, it was specifically localised to the outer layers of the periclinal wall facing the leaf surface, with the thick secondary wall being devoid of silica. Immunocytochemical experiments were performed to ascertain the respective localisation of silica deposition and glycan polymers. Epitopes characteristic for pectic homogalacturonan and the hemicelluloses xyloglucan and mannan were detected in most epidermal walls, including the silica-rich cell wall layers. The monoclonal antibody, LM6, raised against pectic arabinan, labelled the silica-rich primary wall of the epidermal fibre-like cells and the guard cell walls, which were also shown to contain silica. We hypothesise that the silicified outer wall layers of the epidermal fibre-like cells support the lamina during cell expansion prior to secondary wall formation. This implies that silicification does not impede cell elongation. Although our results suggest that pectic arabinan may be implicated in silica deposition, further detailed analyses are needed to confirm this. The combinatorial approach presented here, which allows correlative screening and in situ localisation of silicon and cell wall polysaccharide distribution, shows great potential for future studies.

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The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora.

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Resumo Apresenta-se um estudo taxonômico de Aquifoliaceae para a Serra Negra, Minas Gerais, Brasil. A Serra Negra faz parte do Complexo da Mantiqueira, localizada na porção sul da Zona da Mata Mineira. O inventário florístico foi realizado com base em materiais de expedições vinculadas ao projeto “Estudos Florísticos na Serra Negra”. Essas expedições ocorreram entre 2003 e 2010. Na Serra Negra, Aquifoliaceae está representada por quatro espécies: Ilex dumosa, I. paraguariensis, I. subcordata e I. theezans. São fornecidas descrições, chave de identificação, ilustrações de caracteres diagnósticos e comentários sobre a taxonomia, ecologia e distribuição das espécies.

Resumo O Parque Estadual da Serra do Papagaio está localizado no sul de Minas Gerais, e faz parte do Complexo da Serra da Mantiqueira, com vegetação representada por campos de altitude, floresta ombrófila densa e floresta ombrófila mista. O presente estudo teve como objetivo realizar um tratamento florístico para Verbenaceae nesta Unidade de Conservação. A família está representada no Parque por dez táxons distribuídos em quatro gêneros: Glandularia (G. lobata var. glabrata e G. phlogiflora), Lantana (L. camara e L. fucata), Lippia (L. lupulina, L. rotundifolia, L. stachyoides var. martiana e L. triplinervis) e Verbena (V. alata e V. hirta). Verbena alata destaca-se como nova ocorrência para o estado de Minas Gerais. Lippia rotundifolia e L. stachyoides var. martiana, comuns na Cadeia do Espinhaço, são registradas pela primeira vez na Serra da Mantiqueira, no domínio Atlântico. São apresentadas chaves de identificação, descrições, ilustrações e comentários ecológicos, taxonômicos e de distribuição geográfica dos táxons.