misidentified as Ulva lactuca

Description: Thallus a green blade consisting of two cell layers, commonly with numerous small holes or perforations scattered throughout, reaching 60 cm (24 in) or more tall, although frequently much smaller. Cells are 10-20 μm diameter, and the blade can be 70 μm thick (significantly thicker than Monostroma. Habitat: The species occurs in the mid to low intertidal on cobble, boulders, and bedrock. It prefers protected and semi-protected habitats. Similar taxa: Monostroma, Ulvaria.