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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.

Neptune Grasszoom image
  • Order Najadales
  • Type Perennial
  • Height 12 in (30 cm)
  • Habitat Rocks and sand
  • Distribution Mediterranean
Neptune Grass habitat mapzoom image