Caulerpa nummularia

Thallus light, or pale green consisting of very fine creeping stolons, 0.4-0.8(-1) mm diam., bearing erect branches to 1 cm high and rhizoid-bearing branches. Erect branches simple or branched, with flattened disc-like, peltate blades, 1-3(-5) mm dim., often bearing at the margins (very rarely from center) one or two stalked, peltate discs and the latter giving rise to another. Discs entire, sometimes slightly lobed or crenulate at margins. Rhizoids fine, branched or unbranched. Growing often among algae, such as Amphiroa fragilissima, Jania adhaerens forming dense clumps at sheltered low intertidal, upper subtidal sites on hard substrate.

Note: The alga is used in folk medicine.

Subtropical and tropical waters of Atlantic, Indian and Pacific Oceans. In countries of the Asia-Pacific Region: Japan, China, Vietnam, Philippines, Australia and New Zealand, Pacific Islands.