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Rio de Janeiro, Brazil

Zappi D.C.,Jardim Botanico do Rio de Janeiro
Phytotaxa | Year: 2016

Upon examining material of Loganiaceae for the Brazilian state of Pará, available specimens of Spigelia multispica Steud. were reassessed. In the process, this name and one heterotypic variety were confirmed as synonyms of the older name Spigelia hamellioides Kunth, which had not previously been reported from Brazil, whereas a new name, Spigelia spruceana Zappi, is proposed for Spigelia multispica var. angustifolia Prog. © 2016 Magnolia Press.

da Silva Leal E.,Jardim Botanico do Rio de Janeiro
Nordic Journal of Botany | Year: 2011

A new species, Asplundia altiscandens E. S. Leal from the Brazilian Amazon, is described and illustrated. It belongs to subgenus Asplundia and is related to A. ferruginea and A. nonoensis. Diagnostic characters, a distribution map and taxonomic comments are provided. © 2011 The Author. Nordic Journal of Botany © 2011 Nordic Society Oikos.

Wolowski M.,Programa de Pos Graduacao em Botanica | Ashman T.-L.,University of Pittsburgh | Freitas L.,Jardim Botanico do Rio de Janeiro
PLoS ONE | Year: 2014

Despite the extensive knowledge of pollen limitation in angiosperms, its assessment within tropical forests is still limited. Especially lacking are large scale comparisons of species within this biome - one that is highly diverse but also becoming increasingly threatened. In fact, many tropical plant species depend upon pollinators for reproduction but evaluation of the impact of this dependence via different levels of pollination specialization has yet to be made at the biome scale. We assessed the occurrence and magnitude of pollen limitation for species in the Brazilian Atlantic forest and tested the association of pollination specialization, breeding system, and life habit with pollination efficiency. We compiled data from studies published between 1985 and 2012. We calculated species' effect size (d) from data on fruit set after hand cross-pollination and natural pollination and conducted standard and phylogenetically independent meta-analysis. Overall pollen limitation was moderate, with magnitude of 0.50, and 95% confidence interval [0.37, 0.62] for 126 species. Pollen limitation was observed in 39% of species. Pollination specialization was the factor that best explained the occurrence of pollen limitation. Specifically, phenotypic and ecological specialists (plants with zygomorphic flowers and pollinated by one species of pollinator, respectively) had higher pollen limitation than generalist plants (actinomorphic flowers and pollination by two or more species). Functional generalists (plants pollinated by three or more functional groups) were not pollen limited. On the other hand, breeding system and life habit were not associated to pollen limitation. Pollen limitation was observed in the Atlantic forest and its magnitude was comparable to that for angiosperms as a whole. The finding that pollination specialization was the strongest predictor of pollen limitation suggests that specialist plants in this biome may be most prone to the reproductive failure as a result of pollinator loss. © 2014 Wolowski et al.

Samuel De Avila Jr. R.,Federal University of Ouro Preto | Freitas L.,Jardim Botanico do Rio de Janeiro
Australian Journal of Botany | Year: 2011

In plants pollinated by different groups of animals, the most frequent visitors may not be the most effective for fitness because of their differential efficiency in pollen transfer. We addressed this question by studying a rare dioecious species of Rubiaceae in Brazil. The flowers of Randia itatiaiae are gender-heteromorphic and hypocrateriform with greenish corolla tubes ∼2cm long, and exhale a strong sweet scent during the entire period of anthesis, which starts at sunset for female flowers. Sucrose was the dominant or co-dominant nectar sugar for both genders. In spite of these typical sphingophilous-phalaenophilous traits, the flowers last for 6 days, and nectar was available in both diurnal and nocturnal assessments. Moreover, the flowering of R. itatiaiae did not overlap the phenodynamics of the Sphingidae community. Accordingly, two functional groups of Lepidoptera Hesperiidae during the day and Sphingidae and Noctuidae at night visited the flowers. Visits by either group resulted in equivalent fruit set and seed number per fruit, although the frequency of visits to flowers was higher during the day than at night. Diurnal and nocturnal lepidopterans may exert similar pressures on floral morphology, in addition to divergent pressures on other characters, such as the temporal dynamics of anthesis and nectar production. The pollination system of R. itatiaiae is specialised at the coarse scale, because its floral morphology precludes pollination by animals other than lepidopterans; however, its floral phenotype also represents a generalist compromise between the conflicting pressures exerted by diurnal and nocturnal groups of lepidopterans. © 2011 CSIRO.

Ribeiro K.T.,Instituto Chico Mendes Of Conservacao Da Biodiversidade | Freitas L.,Jardim Botanico do Rio de Janeiro
Biota Neotropica | Year: 2010

The Brazilian campos rupestres and campos de altitude are characterized by mosaics of vegetation types and are better represented above 900 m in the Espinhaço Range and above 1500-2000 m in the Serra do Mar and Serra da Mantiqueira. They bear high species richness at local and regional scales and numerous relicts and endemisms. These montane refuges, which are of particular interest to conservation in various ways, such as recharge and water regulation, control of erosion and sedimentation, biological singularity and recreational and spiritual values, are facing various threats such as erosion and soil instability, urban and agriculture sprawl, fires, removal of ornamental plants and mining. Moreover, these refuges are among the most vulnerable Brazilian ecosystems to global climate change, because the simple fact that with increasing temperature there is no possibility to migrate to higher altitudes. This paper discusses the potential impacts of the proposed new Brazilian Forest Code, currently under discussion in the Congress, for the conservation of biodiversity in these environments. Particularly we analyze the consequences of the removal of areas above 1800 m and on the hill tops as Permanent Preservation Areas (APPs), the reducing on the minimum width of the riparian vegetation and the exemption to smallholders of the conservation of native vegetation on their lands ("Legal Reserves"). Such proposals seem to assume that there is great individual injury on behalf of a very diffuse collective benefit, but do not consider the direct benefits of the current instruments of the Code to rural land owners. The losses of biodiversity and ecosystem services (e.g., water supply, presence of pollinators, natural pest control and timber and non-wood resources) with the conversion of habitat that may result from those changes are disproportionate to the potential economic benefit. The instruments proposed on the new Code, ultimately, lead to a model of space occupation with strong contrasts, it means, fully protected areas, such as parks and biological reserves, alternated with extensive areas devoid of vegetation except thin riparian forests. Such a scenario is detrimental to the conservation of biodiversity and for agricultural production, especially to smallholders, who benefit directly from environmental services.

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