Porphyra Umbilicalis

Porphyra umbilicalis is a species of red algae commonly called laver, known in the Irish Sea region as sleabhac or slake. It forms delicate, sheet-like fronds up to about 25 centimeters long that are only one cell thick, an unusual trait among seaweeds. Though classified as a red alga it typically looks brownish in the wild and turns dark green when prepared for food. It is commonly found around the west coast of Great Britain and the east coast of Ireland along the Irish Sea. Porphyra umbilicalis is edible and is used to make laverbread, but it is classified as critically endangered in parts of the United Kingdom following a steep decline of its population in habitats where it was once established.