Plant
Algae comprise several different groups of organisms which produce food by photosynthesis and thus have traditionally been included in the plant kingdom. The seaweeds range from large multicellular algae to single-celled organisms and are classified into three groups, the brown, red and green algae. There is good evidence that the brown algae evolved independently from the others, from non-photosynthetic ancestors that formed endosymbiotic relationships with red algae rather than from cyanobacteria, and they are no longer classified as plants as defined here.
Desmarestia viridis
Desmarestia viridis is a species of brown algae found worldwide. Its common names include stringy acid kelp, green acid kelp, Desmarest's green weed, and sea sorrel, though the last name can refer to other species of "Desmarestia". The light brown thallus is delicate with a disc-shaped holdfast. It releases sulfuric acid when damaged, destroying itself and nearby seaweeds in the process. They are found in shallow intertidal areas.