Sargassum

'Sargassum' is a genus of brown fucoid algae that grows mostly in subtropical regions around the world. The most famous of these areas is off the coast of the southeastern portion of the North American Continent, where the North Atlantic Subtropical Gyre's anticyclonic rotation swirls free-floating sargassum weed into huge mats on the open ocean in a region called the Sargasso Sea.

This little fragment of it washed ashore on the beach in Puerto Morelos, a small town in the state of Quintana Roo on the Yucatan Penninsula in Mexico, about half an hour south of the city of Cancun.

May 2005, film.