Sargassum Sargassum Sargassum is a genus of brown (class Phaeophyceae) macroalgae (seaweed) in the order Fucales. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs, and the genus is widely known for its planktonic (free-floating) species. Most species within the class Phaeophyceae are predominantly cold-water organisms that benefit from nutrients upwelling, but the genus "Sargassum" appears to be an exception. Any number of the normally benthic species may take on a planktonic, often pelagic existence after being removed from reefs during rough weather; however, two species ("S. natans"
Sargassum muticum observed in temperate environments. "Sargassum muticum" grows from half-tide to infralittoral areas (to a depth of 10 m.). It is fixed on solid substrates like rocks, stones, shells. It is highly tolerant towards temperature and salinity variations. The optimal temperature is between 17 and 20 °C but it tolerates -9 and 30 °C. Originally from Japan, it is thought to have gained worldwide distribution through being transported with Japanese oysters ("Crassostrea gigas"). "Sargassum muticum" was introduced to the Californian coast in the 40's and in Europe in the 70's (The species was first found in the British Isles in the