The seagrass Halophila major (Zoll.) Miguel is reported for the first time from Vietnam. It was found growing with other seagrass species nearshore, 4-6 m deep at Tre Island, Nha Trang Bay. Leaf morphology and phylogenetic analysis based on ribosomal internal transcribed spacer sequences confirmed the identification. There was very little sequence differentiation among samples of H. major collected in Vietnam and other countries in the Western Pacific region. A very low evolutionary divergence among H. major populations was found.Leibniz University Hannover,Government of Vietna
