-(Structure of "cerradão" and transition between "cerradão" and swamp forest, in a fragment of International Paper of Brasil Ltda., in Brotas, SP). The cerrado biodiversity is being seriously threatened by deforestation, since many of its species present restrict geographic distribution. Because of its central position in South American continent, the cerrado has extensive borders with other vegetation types, including swamp forests. We aimed at: 1) knowing the flora and describing the community of shrubs and trees of a cerradão (savanna woodland) and its transition to a swamp forest in Brotas municipality, SE Brazil; 2) investigating the floristic similarity among other cerrado areas in São Paulo State. We found 125 species of 91 genera and 49 families in the fragment surveyed. Myrtaceae and Leguminosae had the highest species richness, a pattern frequently found in other areas of cerrado in São Paulo State. However, only in Brotas, Lauraceae and Euphorbiaceae had a high species richness. We sampled a total of 3,787 individuals (DSH ≥ 3 cm) in one hectare and estimated H' = 3,378 nats.individual -1 . The species with highest Importance Value Indices were Xylopia aromatica, Vochysia tucanorum, Ocotea pulchella, Gochnatia polymorpha, and Myrcia albo-tomentosa. There was no significant correlation between the floristic similarity and the geographical distance among the 10 cerrado areas compared, due the high proportion of common species. The high proportion of common species among cerrado areas in São Paulo State corroborates the results of other authors, who found that it is located on a center of diversity, whose floristic composition is different from the other Cerrado's diversity centers in Brazil.Key words -cerrado, community structure, floristic composition, swamp forest, floristic similarity RESUMO -(Estrutura do cerradão e da transição entre cerradão e floresta paludícola num fragmento da International Paper do Brasil Ltda., em Brotas, SP). A biodiversidade existente no cerrado está seriamente ameaçada pela devastação, pois muitas das espécies que aí ocorrem possuem distribuição geográfica restrita. Pela posição central do cerrado no continente sul-americano, ocorrem associações entre a vegetação do cerrado e outras formações, dentre estas a floresta paludícola. Os objetivos deste trabalho foram conhecer a flora e descrever a comunidade arbustivo-arbórea de um cerradão e da transição entre esse cerradão e uma floresta paludícola em Brotas, e investigar as similaridades e diferenças florísticas entre levantamentos realizados em fisionomias similares no estado de São Paulo. No fragmento ocorreram 125 espécies de 91 gêneros e 49 famílias. Myrtaceae e Leguminosae foram as famílias mais ricas em espécies, um padrão consistente com o encontrado em outros levantamentos nos cerrados paulistas. Somente em Brotas, Lauraceae e Euphorbiaceae apresentaram alta riqueza específica. No levantamento fitossociológico, em 1,0 ha, foram amostrados 3.787 indivíduos com DAS ≥ 3 cm (H' = 3,378 nats.indivíduo -1 ). As es...

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Testing the quick meal hypothesis: The effect of pulp on hoarding and seed predation of Hymenaea courbaril by red-rumped agoutis (Dasyprocta leporina) Abstract: Red-rumped agoutis (Dasyprocta leporina) are important seed dispersers/predators of Neotropical large-seeded plants. Several species of seeds cached by agoutis have an edible reward, in contrast to temperate rodent-dispersed diaspores. The quick meal hypothesis states that the presence of a reward such as edible pulp will enhance the efficiency of rodents as seed disperses by satiating the animal and, consequently, reducing seed predation and enhancing hoarding. In this study, this hypothesis was tested using as the reference system the pulp and seeds of Hymenaea courbaril. Seeds with and without pulp were offered to agoutis and the behaviour of each individual was recorded. Since the probability of predation and hoarding were complementary, we used the probability of predation. The proportion of agoutis that preyed on at least one seed was similar for seeds with (42.8% of individuals) and without (40.0% of individuals) pulp. In agoutis that preyed upon at least one seed, the probability that they killed a seed did not differ between seeds with (0.17 ± 0.03) and without (0.20 ± 0.08) pulp. Hence, these results do not support the 'quick meal hypothesis'.

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