Codium repens

Thallus spongy, gregarious, prostrate, forming extensive mats to 20 cm in diam., to 5 cm in height, dull green to dark green. Branching dichotomous to irregular. Branches cylindrical or slightly flattened, 2-3(-4) mm wide often fusing together. Utricles cylindrical, club-shape, (60)-100-300(-330) μm diam., 580-800 μm long. Apices rounded, slightly flattened. Apical wall thickened to 15 mm. Hairs or hair scars common, 1(-2) per utricle, (80)-100-120 mm below the apex. Gametangia oval, spindle-like, 50-100(-105) mm diam., 240-300(-340) mm long, stalked (to 30 mm long), borne below apex (250)-300(-340) mm, one per utricle. Growing on middle to lower intertidal hard substrates, dead corals, to 2-5 m deep.

Note: The alga is used in folk medicine (antimicrobial, antifungal).

Atlantic, Indian and Pacific Oceans. Common in countries of the Asia-Pacific Region: China, Korea, Vietnam, Pacific Islands.