Shells of the limpet Patella aspera as habitat for epibionts

World Congress of Malacology, Universidade dos Açores, Ponta Delgada, 21-28 de julho.

Although limpets can control the abund ance and distribution of algae and other organisms, their shells can offer a refuge for the establishment of diverse assemblage that would otherwise be excluded. In this study, we make a preliminary analysis of the epibiota growing on shells of the limpet Patella aspern. Individuals of P. aspera were collected in all islands of the Azores and the biota on their shells was identified and quantified to species leveli. A total of 144 species was identified. The composition of the epibiota assemblage varied among islands and among locations within islands. There was also significant variation in epibiota richness at the scale of locations, but not at the scale of islands. A positive and highly significant correlation was also found between epibiota richness and shell length. This study adds to the literature by showing that the shells of P. aspern, an over-exploited species in the Azores, support a very rich community of algae and invertebrates and that this is controlled by processes operating at multiple spatial scales ranging from metres (among individuals) to 100's of kilometers (among islands).