Distribution and species composition of the littoral interstiticial free living nematodes in the northern Red Sea, Egypt

Free living nematodes represent the most abundant and diversified group of the interstitial meiobenthos in the northern Red Sea, where their contribution ranged between 38 and 100% of total count of all interstitial organisms. Nematodes distribution, abundance and species composition in the Egyptian Red Sea were studied during winter, 2006. Nematodes abundance ranged between 8 and 163 organisms/10 cm^2. The intertidal zonation was investigated and showed increasing in the average density of nematodes toward low tide mark (sublittoral zone). A total of 79 nematode species were recorded; xyalid and oncholaimid were the most abundant families contributing 12% for each of total nematodes count. Densities of nematodes were affected by the grain size of the sediment, TOMs and redox potential (Eh). Also, pollution and landfilling have the most drastic effect on their abundance and diversity.