INOC-CNRS, International Conference on “Land-Sea Interactions in the Coastal Zone” Jounieh - LEBANON, 06-08 November – 2012 140 DISTRIBUTION OF ROCKY INTERTIDAL MOLLUSCS IN QESHM ISLAND, THE PERSIAN GULF Fatemeh Amini Yekta 1* , Sahar Izadi 2 , Mitra Asgari 3 1 Iranian National Institute for Oceanography (INIO), Tehran, I. R. Iran 2,3 Persian Gulf Biotechnology Park and Research Centre, Qeshm Island, Persian Gulf, I. R. Iran E-mail* : fateme.yekta@gmail.com ABSTRACT Mollusc’s community was investigated along 9 intertidal rocky sites around Qeshm Island in August 2010 and January 2011. This survey is a part of a comprehensive study on intertidal invertebrates of Qeshm Island carried out in Persian Gulf Biotechnology Research Centre. In total, 69 taxa belonging to 37 families and 3 classes (gastropoda, bivalvia and polyplacophora) were identified in sampling sites. Differences in mollusc’s biodiversity among sites were studied by depicting dissimilarities of sampling sites according to presence and absence of mollusc species. The results of MDS and cluster analysis displayed clear groups which can be explained by specific characters of sampling sites such as distance to residential area or situation of locations in island. The results of cluster analysis confirmed this grouping as well. In 0.48 similarities, MDS plot showed two distinct groups that separated location 16 and location 24 from other sites. In contrast to other sampling sites, these two sites are located in northern part of the island. Location 5, which is a pristine site, with 35 species showed the most mollusc diversity, while location 16, which is exposed to fisheries activities by locals, was the least diverse site with 19 species. Clypeomorus bifasciatus was found in all sampling sites, while Engina mendicaria, conus sp., Mauritia grayana, Diodora sp., Meduso fissurella sp., Littoraria intermedia, Thais tissoti, Nerita adenensis, Cellana rota, Gryneum sp., Barbatia obliquata, Vasticardium lacunosum, Plicatula plicata, Codakia tigerina, Asaphis violascens, Neotrapezium sublaevigatum, Irus macrophylla, Chiton lamyi, Chiton salihafui and Tonicella sp. was sampled just in one of these 9 sites. Keywords: Mollusca, Qeshm Island, Persian Gulf, Biodiversity 1. INTRODUCTION Coastal marine ecosystems have great economic importance due to the fishing opportunities, recreation and other services they provide. However, there is little known about the biogeographical patterns of coastal marine species [1].The coasts of the Persian Gulf are no exception regarding the lack of information. Qeshm Island, as the largest island of the Persian Gulf, with 120 km length and up to 30 km width, is located in the western part of the Strait of Hormuz [2]. This island receives fresh and nutrient rich oceanic water through the Strait of Hormuz which leads to a large biodiversity and various substrates. The possible human effects on the invertebrate fauna along the Iranian coast of the Persian Gulf are difficult to assess since this fauna is not still known adequately [3]. Biodiversity and abundance of macroinvertebrates