Posidonia Oceanica

Posidonia oceanica is an aquatic plant, endemic to the Mediterranean, belonging to the Posidoniaceae family. It has characteristics similar to land plants, such as roots, rhizomatous stem and cyntiform leaves up to one meter long arranged in clumps of 6 to 7. It blooms in autumn and produces floating fruits commonly known as sea olives in spring. (See more on Wikipedia)

It forms seagrass meadows that are of remarkable ecological importance. It is the climax community of the Mediterranean Sea and plays a considerable role in protecting the coastline from erosion. Many animal and plant organisms live within them that find food and protection in the meadows. It is considered a good bioindicator of the quality of coastal marine waters.