Estudio ecológico estacional de los moluscos de la Ría de Ares y Betanzos (Galicia, NO España)

An analysis of the molluscan fauna of the Ría de Ares y Betanzos (NW Spain) was made. Samples were taken seasonally in five stations located at the median-inner part of the ría. Sandy and muddy bottoms were compared using the relative values of the reported molluscs. From this study it is concluded that grain-size fractions, especially fine sand, silt and clay, and the bottom water temperature are the most important environmental factors influencing the composition and distribution of molluscs.