The ecology of seed dispersal is critical to understand the patterns of distribution and abundance of plant species. We investigated seed dispersal aspects associated with the high abundance of Buchenavia tomentosa in the Serra Azul State Park (PESA). We estimated fruit production and conducted fruit removal experiments. We carried out diurnal and nocturnal observations on frugivory as well as germination tests. Fruiting occurred in the dry season and totaled 1,365,015 ± 762,670 fruits.ha -1 . B. tomentosa fruits were utilized by eight animal species. The lowland tapir (Tapirus terrestris) was considered the main seed disperser. Leafcutter ants (Atta laevigata and Atta sexdens) participated in the seed cleaning and occasionally dispersed seeds. The beetle Amblycerus insuturatus, blue-and-yellow macaw (Ara ararauna) and red-and-green macaw (Ara chloropterus) were considered pre-dispersal seed predators. The seeds manually cleaned presented higher germination rate (100%) and speed index (4.2 seeds.d) than that of seeds with pulp. Germination of seeds found in tapirs'feces was 40%, while for the seeds without pulp it was 25%. The high abundance of B. tomentosa in the cerrado of PESA may be due to massive fruit production, low rates of seed predation, and efficient seed dispersal by tapirs, occurring before the rains which promote germination and recruitment of this species.Keywords: exclusion experiments, fruit production, frugivory, seed germination, tapir dung. Dispersão e predação de sementes de Buchenavia tomentosa Eichler (Combretaceae) em Cerrado sentido restrito, centro-oeste do Brasil ResumoA ecologia da dispersão de sementes é importante para entender a distribuição e abundância das espécies vegetais. Investigamos os fatores relacionados à elevada abundância de B. tomentosa no Parque Estadual da Serra Azul (PESA) avaliando aspectos da dispersão de sementes. Estimamos a produção de frutos e realizamos experimentos de remoção de frutos. Fizemos observações diurnas e noturnas sobre a frugivoria e testamos a germinação de sementes. A frutificação ocorreu na estação seca totalizando 1.365.015 ± 762.670 frutos.ha -1 . Oito espécies de animais utilizaram frutos de B. tomentosa. Anta (Tapirus terrestris) foi considerada o principal dispersor. Saúvas (Atta laevigata e Atta sexdens) participaram na limpeza das sementes e como dispersores ocasionais. O besouro Amblycerus insuturatus, arara-canindé (Ara ararauna) e arara-vermelha (Ara chloropterus) foram considerados predadores pré-dispersão. Sementes despolpadas manualmente tiveram maior percentual (100%) e velocidade de geminação (4,2 sementes.dia -1 ) que aquelas com polpa. Sementes encontradas nas fezes de antas apresentaram 40,0% de germinação e sementes sem polpa 25,0%. A massiva produção de frutos, baixa taxa de predação de sementes, além da eficiente dispersão por antas, antes da estação chuvosa, favorecem o recrutamento e são fatores que contribuem de forma decisiva para a elevada abundância de B. tomentosa observada no cerrado do PESA.Palavras-chave:...

Oviposition and predation levels by Speciomerus revoili bruchid beetles were quantified on fruits and seeds of the macaúba palm, Acrocomia aculeata, collected from below mother-trees within the Sarah Kubitschek Park of Brasília, DF, Brazil. A maximum of 12 eggs per fruit were found, with high variations observed between samples. No clear pattern was found for the distribution of the number of eggs per fruit, perhaps due to the artificial conditions of the study area, the absence of dispersers and/or the plasticity in the oviposition behavior of the insect. The number of eggs per fruit was not related to fruit size, but was associated with their availability under the tree-mother. This suggests that the density of eggs per fruit is a balance between the availability of this resource and the number of females in the beetle population. The observed mortality rate, from the egg phase to the final larval stages, was over 75%. About 40% of the seeds of Acrocomia aculeata were predated by Speciomerus revoili.

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As sessile organisms, bryozoans are among the commonest components of the encrusting communities on hard substrata. On unconsolidated bottoms, benthic animals and their carapaces, including mollusk shells, represent potential surfaces for encrustation. Here we describe the bryozoan fauna growing on disarticulated bivalve shells collected intertidally on Itaparica beach, Todos os Santos Bay, northeast Brazil. We examined a total of 382 valves representing seven species of bivalves, among which we found 82 valves of three bivalve species to be encrusted by bryozoans, with 109 bryozoan colonies detected overall. We identified 11 cheilostome bryozoan species, among which Phidoloporidae and Smittinidae were the most diverse, with four and two species, respectively. We redescribed two bryozoan species, Parasmittina loxoides and Rhynchozoon phrynoglossum, and describe another two, Pleurocodonellina marcusi n. sp. and Rhynchozoon itaparicaensis n. sp., as new. A new combination for Cribella triangulata Canu & Bassler, 1928 is proposed, including Calyptotheca tenuata Harmer, 1957 as a new junior subjective synonym of Calyptotheca triangulata n. comb. All but one of the 11 species have encrusting colonies; Licornia aff. diadema, forms erect branching colonies. For seven of the bryozoans, ours are the first records of these species growing on shells. Although the majority of bryozoans we studied have also been reported on other substrata, Rhynchozoon brasiliensis and Parasmittina loxoides were predominant in the fauna, comprising 79 (72%) of all colonies inventoried. Due to the lack of information on the distribution of these species in northeastern Brazil, further studies are needed to determine whether they show any substratum preference.