Description: Thallus is tubular, although it can appear filamentous because of its narrow diameter. Branches proliferate from the tube. It forms extensive mats several meters (many feet) in length. The color can range from grass green to very light green. Habitat: This species is found on protected beaches attached to cobble or smaller substrates, or free-floating in muddy areas in summer. Similar taxa: Cladophora sericea, Ulva spp.