Distribuição de Teredinidae Rafinisque, 1815 (Mollusca: Bivalvia) ao longo da costa sudeste do Brasil

Abstract

The distribution of teredinid wood-boring molluscs along part of the southeast coast of Brazil was studied. The infestation levels were correlated to ecological factors such as wood supply, and the presence of fouling or competitor organisms. The hypothesis tested was: there is an infestation gradient as well as a difference in the specific composition of teredinids along part of the southeast coast of Brazil which may be related to ecological factors such as availability of wood and the presence of fouling organisms or other competitors. Nine sites were considered from São Sebastião, state of São Paulo, to Vitória, state of Espírito Santo (23º 45'36"S, 45° 24'35"W a 20° 19'10"S, 40° 20'16"W). Teredinids were obtained from pinewood paneis immersed for 3 to 6 months intervals during the one year experiment. Seven species of teredinids were found: Bankia carinata, Bankia .ftmbriatula, Bankia gouldi, Lyrodus floridanus, Nototeredo knoxi, Teredo bartschi e Teredo furcifera. Infestation leveis were, in general, decreasing from south to north. This gradient was mainly related to the availability of wood from the surrounding vegetation (rainforest, Serra do Mar). No infestation was recorded in Urca, state of Rio de Janeiro, or Vitória. Paneis immersed in the first station presented a high percent cover of fouling organisms while the latter was dominated by the space competitor crustacean Limnoria tripune/ata. The dominant species in the southem stations was Bankia gouldi. Northem stations showed no common dominating species. Differences related to infestation and specific composition along the southeast coast can be correlated to local factors.