see text Conchocelis Batters 1892 Phyllona J.Hill 1773 Porphyra is a genus of coldwater seaweeds that grow in cold, shallow seawater.

In East Asia, it is used to produce the sea vegetable products nori (in Japan) and gim (in Korea).

The fertilized, now diploid, carposporangia after mitosis produce spores (carpospores) which settle, then bore into shells, germinate and form a filamentous stage.

[2][8] Most human cultures with access to Porphyra use it as a food or somehow in the diet, making it perhaps the most domesticated of the marine algae,[9] known as laver, rong biển (Vietnamese), nori (Japanese:海苔), amanori (Japanese),[10] zakai, gim (Korean:김),[10] zǐcài (Chinese:紫菜),[10] karengo, sloke or slukos.

[12] Porphyra was also harvested by the Southern Kwakiutl, Haida, Seechelt, Squawmish, Nuu-chah-nulth, Nuxalk, Tsimshian, and Tlingit peoples of the North American Pacific coast.