Fucus Vesiculosus

Fucus vesiculosus, commonly called bladderwrack or rockweed, is a brown alga in the order Fucales, found on rocky coasts of the North Sea, the western Baltic Sea, and the Atlantic and Pacific Oceans, from the Atlantic shores of Europe and northern Russia to Greenland, the Azores, and the Atlantic coast of North America. Its fronds grow up to 150 centimeters long and 2.5 centimeters wide, marked by a prominent midrib and branching dichotomously, and typically carry paired, almost spherical air bladders on either side of the midrib. The species was the original source of iodine, discovered in it in 1811, and was used extensively to treat goitre, a thyroid condition linked to iodine deficiency.