Publications by authors named "Joao R Stehmann"

Augsten & Stehmann (Solanaceae), , a small 'tobacco' known only from one locality at Serra do Gandarela, in the state of Minas Gerais, Brazil, is described and illustrated. It is morphologically characterized by its rosulate basal leaves, red corolla with a short tube not inflated at the apex, and the peculiar habitat, a shaded site under a rocky outcrop ledge along a forested stream. Phylogenetic analyses based on a combined dataset of nuclear (ITS) and plastid (, , and ) DNA sequences revealed that the species belongs to the Nicotianasect.

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Premise: Evolutionary studies require solid phylogenetic frameworks, but increased volumes of phylogenomic data have revealed incongruent topologies among gene trees in many organisms both between and within genomes. Some of these incongruences indicate polytomies that may remain impossible to resolve. Here we investigate the degree of gene-tree discordance in Solanum, one of the largest flowering plant genera that includes the cultivated potato, tomato, and eggplant, as well as 24 minor crop plants.

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Two new species of Sendtn. (Solanaceae) from the Brazilian Atlantic Forest are described and illustrated. I.

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Ethnopharmacological Relevance: species of Terminalia (Combretaceae) are used to treat diabetes and metabolic disorders in Asia, Africa, and America. Terminalia phaeocarpa Eichler is an endemic tree from Brazil, popularly known as capitão. This species is closely related to Terminalia argentea Mart.

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The Solanum glaucophyllum Desf. has been used to treat and prevent diseases in human and veterinary medicine. On the other hand, plant poisoning causes several bone diseases, among them osteoporosis, which is characterized by osteoblastic hypoplasia.

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Barboza & Bianchetti , a species from mid-elevation of the Atlantic Forest (Minas Gerais, Brazil) is described and illustrated. This endemic new species is distinguished from the most similar Mart. by its moderate to dense general pubescence, narrowly elliptic leaves and larger calyx appendages and corollas.

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Gouvêa & Giacomin, , is described from central Brazilian Atlantic Forest. It is known from only three localities in Espírito Santo and Minas Gerais states, where granitic/gneissic outcrops (inselbergs or sugar loaves) are ubiquitous. The new species, here described, belongs to Solanum subgenus Leptostemonum (or the Leptostemonum clade; i.

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The hexane and ethanol extracts from (Apocynaceae) stems were evaluated for antiviral activity against Zika virus, yellow fever virus and dengue virus 2 and for cytotoxicity in Vero cells by MTT assay. The ethanol extract showed good antiviral activity against the three viruses with selective indexes (SI) > 10 and its fractionation led to the isolation of the known plumieride that was active only against Zika virus (SI of 15.97).

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Traditional conservation techniques for mapping highly biodiverse areas assume there to be satisfactory knowledge about the geographic distribution of biodiversity. There are, however, large gaps in biological sampling and hence knowledge shortfalls. This problem is even more pronounced in the tropics.

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A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

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Recent debates on the number of plant species in the vast lowland rain forests of the Amazon have been based largely on model estimates, neglecting published checklists based on verified voucher data. Here we collate taxonomically verified checklists to present a list of seed plant species from lowland Amazon rain forests. Our list comprises 14,003 species, of which 6,727 are trees.

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Although Brazil is a megadiverse country and thus a conservation priority, no study has yet quantified conservation gaps in the Brazilian protected areas (PAs) using extensive empirical data. Here, we evaluate the degree of biodiversity protection and knowledge within all the Brazilian PAs through a gap analysis of vertebrate, arthropod and angiosperm occurrences and phylogenetic data. Our results show that the knowledge on biodiversity in most Brazilian PAs remain scant as 71% of PAs have less than 0.

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A new section of Eugenia (Myrtaceae) is described, segregate from Eugenia sect. Phyllocalyx. Phylogenetic studies suggest that Eugenia sect.

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A new species of Solanum (Solanaceae) from the Geminata clade is described for the Brazilian flora. Solanum lagoense Stehmann is only known from Lapinha, a rocky massif located in the Lagoa Santa karst region of Minas Gerais State. The flora of this area, including Solanaceae, was studied in detail in the second half of the 19(th) century by the Danish botanist Eugene Warming.

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Knowledge of the geographic distribution of plants is essential to underpin the understanding of global biodiversity patterns. Vascular epiphytes are important components of diversity and functionality of Neotropical forests but, unlike their terrestrial counterparts, they are under-represented in large-scale diversity and biogeographic analyses. This is the case for the Atlantic Forest - one of the most diverse and threatened biomes worldwide.

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We submitted tree species occurrence and geoclimatic data from 59 sites in a river basin in the Atlantic Forest of southeastern Brazil to ordination, ANOVA, and cluster analyses with the goals of investigating the causes of phytogeographic patterns and determining whether the six recognized subregions represent distinct floristic units. We found that both climate and space were significantly (p ≤ 0.05) important in the explanation of phytogeographic patterns.

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Addressing the challenges of biodiversity conservation and sustainable development requires global cooperation, support structures, and new governance models to integrate diverse initiatives and achieve massive, open exchange of data, tools, and technology. The traditional paradigm of sharing scientific knowledge through publications is not sufficient to meet contemporary demands that require not only the results but also data, knowledge, and skills to analyze the data. E-infrastructures are key in facilitating access to data and providing the framework for collaboration.

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Two additions and four new species are described from Brazil for the large Geminata clade (Solanum: Solanaceae) bringing the total diversity in the group to 149 species, with 44 of these occurring in Brazil. New species are described from Brazil: Solanumamorimii S.Knapp & Giacomin, sp.

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Three new Brazilian species of the Brevantherum clade of Solanum (Solanaceae) are described, all closely related to the poorly known Solanum inornatum Witasek. Solanum bradei Giacomin & Stehmann, sp. nov.

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There is a consensus that plants are great sources of metabolites with a broad variety of functions. This is particularly important because plants cannot run away from environmental conditions that can threat their existence. The numerous biological activities exhibited by plant natural products prompted humanity to use such substances or their derivatives for the treatment and/or prevention of diseases.

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A new species of Solanum from Brazil is described. Solanum evolvuloides Giacomin & Stehmann, sp. nov.

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The workshop 'Species distribution models: applications, challenges and perspectives' held at Belo Horizonte (Brazil), 29-30 August 2011, aimed to review the state-of-the-art in species distribution modelling (SDM) in the neotropical realm. It brought together researchers in ecology, evolution, biogeography and conservation, with different backgrounds and research interests. The application of SDM in the megadiverse neotropics-where data on species occurrences are scarce-presents several challenges, involving acknowledging the limitations imposed by data quality, including surveys as an integral part of SDM studies, and designing the analyses in accordance with the question investigated.

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In the Southern and Southeastern Brazilian highlands, a clade of seven species of Petunia that are endemic to the region (P. altiplana, P. bonjardinensis, P.

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Intrinsic reproductive barriers among the species of Petunia are weak and genetic isolation is obtained mainly by geographical separation and ecological diversification. The Serra do Sudeste region in the extreme south of Brazil is one of the centres of diversity of this genus and is characterized by the presence of species with different pollination syndromes. Petunia exserta is known only from four sandstone towers in a restricted area of this region (about 500 km(2)) and is characterized by its differentiated habitat (shelters in the sandstone towers) and by its floral characteristics adapted to ornithophily.

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Representatives from 11 Petunia Jussieu species in south and southeast Brazil were compared with two Calibrachoa La Llave & Lex., one Bouchetia Dunal, and two Nierembergia Ruiz & Pav. taxa in relation to DNA molecular variability.

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