Mollusca fauna from infralittoral hard substrate assemblages in the North Aegean Sea

The spatial distribution of the molluscan fauna from infralittoral hard substrate assemblages in the North Aegean Sea was studied during summer 1997 and 1998. Material was collected from six stations located in Chalkidiki peninsula, plus one in Kavala Gulf. Samples were collected by means of SCUBA diving (5 replicates with a quadrate sampler covering the surface of 400cm(2)). Examination of the 10917 living molluscs collected revealed 111 species, belonging to three different classes (five Polyplacophora, 85 Gastropoda and 21 Bivalvia). Skeneopsis planorbis, Trapania maculata and Limapontia capilata are reported for the first time as elements of the molluscan fauna in the Eastern Mediterranean or the Aegean Sea, and Callistochiton pachylasmae, Raphitoma leufroyi, Polycera quadrilineata, Phyllaplysia lafonti and Petalifera petalifera as elements in the North Aegean Sea. Multivariate analyses (Cluster and MDS), discriminate the sampling stations into four main groups, indicating, that apart from the rough dispersion of the molluscs, a more homogenous pattern is detectable at the middle part of the lower infralittoral zone.