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Previous issue date: 2014-02-28 === CAPES === CNPq === Submerged structures composed of wood are deteriorated by the activity of molluscs and crustaceans borers. Among these, the teredinids (Mollusca, Bivalvia) are the most specialized marine borers, leading to huge economic losses. On the other hand, these wood-boring organisms are the most important decomposers agents of timber in estuarine regions. Comprehend the influence of environmental factors on the occurrence and dynamics of teredinids taxocenosis is critical to the zoological and ecological knowledge of the family. The present study was conducted in the estuary of Marambaia, Rio de Janeiro, RJ, aiming to conduct the survey of species of teredinids by using specialized test panels. The species distribution was correlated with levels of salinity along the estuary and monthly volumes of precipitation. Wood consumption was estimated by a novel method. Permanently flooded and periodically flooded regions (mangrove forests) were compared by the occurrence of teredinids and wood consumption, as well as test panels exposed to the environment for different periods of time. Five species of teredinids were identified: Bankia gouldi (Bartsch, 1908), Bankia fimbriatula (Mol; Roch, 1931), Lyrodus floridanus (Bartsch, 1922), Nototeredo knoxi (Bartsch, 1917) and Teredo furcifera (Linnaeus, 1758). The most abundant specie was B. fimbriatula (47.31%), followed by B. gouldi (41.15%). Only two individuals of N. knoxi were found. The nearest sea point and points on permanently flooded sites had higher numbers of species, higher abundances of individuals and higher rates of wood consumption. The different periods of exposure of the test panels to the environment did not change the configuration of teredinids? colonization, nor the rates of wood consumption. An inverse correlation was found between rainfall and the number of individuals throughout the experiment, but the effects of rainfall were felt belatedly by the organisms. No significant correlation between salinity and the distribution of the teredinids was found, however, the data pointed to the role of salinity as the determinant factor of the species? occurrence and of the taxocenosis? characteristics along the Marambaia estuary. === Estruturas submersas compostas por madeira s?o deterioradas pela atividade de moluscos e crust?ceos perfurantes. Entre estes, os teredos (Mollusca, Bivalvia) s?o os perfurantes marinhos mais especializados, causando enormes preju?zos econ?micos. Por outro lado, estes organismos s?o os mais importantes agentes decompositores de madeira em regi?es estuarinas. Compreender a influencia de fatores ambientais sobre a ocorr?ncia e din?mica da taxocenose de teredos ? fundamental para o conhecimento zool?gico e ecol?gico da fam?lia. O presente estudo foi realizado no estu?rio da Marambaia, Rio de Janeiro, RJ, com o objetivo de realizar o levantamento de esp?cies de teredo utilizando coletores especializados. A distribui??o das esp?cies foi correlacionada com os n?veis de salinidade ao longo do estu?rio e volumes mensais de precipita??o. O consumo de madeira foi estimado por um novo m?todo. Regi?es permanentemente alagadas e periodicamente alagadas (bosques de manguezal) foram comparadas quanto ? ocorr?ncia de teredos e consumo de madeira, assim como coletores expostos ao ambiente por diferentes per?odos de tempo. Cinco esp?cies de teredos foram identificadas: Bankia gouldi (Bartsch, 1908), Bankia fimbriatula (Moll; Roch, 1931), Lyrodus floridanus (Bartsch, 1922), Nototeredo knoxi (Bartsch, 1917) e Teredo furcifera (Linnaeus, 1758). A esp?cie mais abundante foi B. fimbriatula (47,31%), seguida de B. gouldi (41,15%). Somente dois indiv?duos de N. knoxi foram encontrados. O ponto mais pr?ximo do mar e os pontos em locais permanentemente alagados apresentaram maior ocorr?ncia de esp?cies, maiores abund?ncias de indiv?duos e de taxas de consumo de madeira. Os diferentes tempos de exposi??o dos coletores ao ambiente n?o alteraram a configura??o de coloniza??o dos teredos e nem o consumo de madeira. Foi encontrada uma correla??o inversa entre a precipita??o e o n?mero de indiv?duos ao longo do experimento, por?m os efeitos da precipita??o foram sentidos tardiamente pelos organismos. N?o foi encontrada uma correla??o expressiva entre a salinidade e a distribui??o dos teredos, por?m os dados apontam para seu papel como fator determinante da ocorr?ncia de esp?cies e das caracter?sticas da taxocenose ao longo do estu?rio da Marambaia.
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