Abstract
On its route from the Mediterranean in the north to the Red Sea in the south, the Suez Canal crosses three different lakes which represent different habitats, and in some cases, hinder the migration of the fauna and flora from one sea to the other. Tintinnid species-specific abundance was determined at monthly intervals from 10 stations in the Suez Canal. A total of 18 species were recorded in the canal water, all Indo-Pacific in origin. Six of these species have been introduced to the Mediterranean, while 11 are new geographical records for the Suez Canal. Most species exhibited a seasonal cycle with low winter and high spring and summer densities. Tintinnid affinities and differences between the eastern Mediterranean and the Red Sea were discussed in the light of the results of distribution studies of the eighteen species of Tintinnid carried out over a complete year. These observations point to the role of the canal as a selective barrier and/or as a link in the migration of Tintinnid protozoa. While cases of migration from one sea to the other are more likely to occur in either direction, those concerning species of Indo-Pacific origin are more successful and numerous. Meanwhile, the Suez Canal acts as a local endemic habitat by itself.