Sargassum that also can mean all seaweed species washed up on shore. "Sargassum" species are found throughout tropical areas of the world and are often the most obvious macrophyte in near-shore areas where "Sargassum" beds often occur near coral reefs. The plants grow subtidally and attach to coral, rocks, or shells in moderately exposed or sheltered rocky or pebble areas. These tropical populations often undergo seasonal cycles of growth and decay in concert with seasonal changes in sea temperature. In tropical "Sargassum" species that are often preferentially consumed by herbivorous fishes and echinoids, a relatively low level of phenolics and tannins
Sargassum color and consist of a holdfast, a stipe, and a frond. Oogonia and antheridia occur in conceptacles embedded in receptacles on special branches. Some species have berrylike gas-filled bladders that help the fronds float to promote photosynthesis. Many have a rough, sticky texture that, along with a robust but flexible body, helps it withstand strong water currents. Large, pelagic mats of "Sargassum" in the Sargasso Sea act as one of the only habitats available for ecosystem development; this is because the Sargasso Sea lacks any land boundaries . The Sargassum patches act as a refuge for many species in different