Translation of "posidonia" into Basque

Plant with elongated, planar, green leaves which measure up to 1,5 m. The flowers come out in the autumn but not every year. The fruits are dark balls. The leaves wilt and separate from the plant at the end of summer. It grows on sandy substrates, and has a rhizome from which several plants grow. The compact form of its growths retains the sediments pulled by the currents along the sea bed. Neptunegrass forms extensive prairies, always on the continental shelf. (Source: DDGI) [..]