Vasillis Papathanasiou
Posidonia oceanica (L.) Delile
Posidonia oceanica the marine plant that causes unwarranted fear in so many swimmers that say "do not swim above the seaweed," is an Angiosperm monocotyledon and not a seaweed (alga). It is more widely known as Poseidonia, as god Poseidon had chosen it as its favorite plant in antiquity.