Marine Animal Encyclopedia
Neptune Grass Posidonia Oceanica
Neptune grass (also known as Mediterranean tapeweed) forms meadows from shallow water to a depth of 150 ft (45 m) in the clearest waters. It grows on both rock and sand, and has a tough, fibrous base and persistent rhizomes (stems) that grow both horizontally and vertically. These build up into a structure known as “matte,” which can be several yards high and thousands of years old. Around the island of Ischia, Italy, more than 800 species have been associated with Neptune grass beds.