318 resultados para eastern Asian endemic genera


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The present study describes the species of Canomaculina Elix & Hale and Parmotrema A. Massal. occuring in Curitiba, Paraná. Identification keys, descriptions of the species, and comments are presented. Canomaculina conferenda (Hale) Elix, Canomaculina pilosa (Stizemb.) Elix & Hale, Parmotrema catarinae Hale and Parmotrema eciliatum (Nyl.) Hale are reported for the first time to Paraná State.

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One dune habitat in the semi-arid Caatinga Biome, rich in endemisms, is described based on plant species composition, woody plant density, mean height and phenology and a multivariate analysis of the micro-habitats generated by variables associated to plants and topography. The local flora is composed mainly by typically sand-dweller species of Caatinga, suggesting the existence of a phytogeographic unity related to the sandy areas in the Caatinga biome, which seems to be corroborated by faunal distribution. Moreover, some species are probably endemic from the dunes, a pattern also found in vertebrates. The plant distribution is patchy, there is no conspicuous herbaceous layer and almost 50% of the ground represents exposed sand. Phenology is not synchronized among species, occurring leaves budding and shedding, flowers development and anthesis, fruits production and dispersion both in rainy and dry seasons. Leaf shedding is low compared to the level usually observed in Caatinga areas and about 50% of the woody individuals were producing leaves in both seasons. Spectrum of dispersal syndromes shows an unexpected higher proportion of zoochorous species among the phanerophytes, accounting for 31.3% of the species, 78.7% of the total frequency and 78.6% of the total density. The habitat of the dunes is very simple and homogeneous in structure and most of environmental variance in the area is explained by one gradient of woody plants density and another of increase of Bromelia antiacantha Bertol. (Bromeliaceae) and Tacinga inamoena (K. Schum.) N.P. Taylor & Stuppy (Cactaceae) toward valleys, which seem to determine two kinds of protected micro-habitats for the small cursorial fauna.

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Seed predation of Virola bicuhyba (Myristicaceae) was studied in an area of Atlantic forest in south-eastern Brazil, with the objective of testing the Janzen-Connell model. The predation of seeds was evaluated at three different distances from the parent tree for two classes of predators: invertebrates and vertebrates. The method of exclosure plots (closed plots) and open control plots was used, distributed at 5, 15 and 25 m from the trunk of each adult fruiting tree of V. bicuhyba. In Experiment 1, 1,200 seeds were used and, in Experiment 2, 1,440 seeds. Both experiments did not agree with Janzen-Connell model, as seed predation by invertebrates and vertebrates was independent of the distance from the parent tree. Seed predation rate was high, however the impact of predation by vertebrates was higher than by invertebrates, indicating that it is the main cause of seed mortality.