Benthos of Iranian parts of the Caspian Sea

The Caspian Sea, which accounts for 40 to 44% of the total lacustrine waters of the world, is still suspected to be referred to as a sea or lake. Because of high biodiversity in the Caspian Sea and its coastal zone, it is one of the most valuable ecosystems on the earth. As this region has been isolated from other water bodies for a long term, high level of endemism is remarkably evident in its fauna. The existence of shallow areas, several deep depressions, and a wide range of salinities varying from 0.1‰ to 13‰ provide different ecological niches, giving rise to high species diversity.