Rhipidosiphon javensis

Thallus blade-like, erect, small 1-2(-3) cm high, mostly solitary, rarely gregarious, bright green when young, whitish-green when older. Blades fan-shaped, delicate, fragile, wedge-shaped at base, rotundate and often lacerate above, monostromatic, lightly calcified, consisting of repeatedly dichotomously branched filaments (siphons) unevenly constricted above dichotomies. The siphons 40–50 mm diam., adhering laterally, with blunt apices. Stalk ~2-7 mm high, simple, monosiphonous, smooth, uncorticated, and not calcified. Attachment by fine shallowly lobed transparent rhizoids. Growing in the middle, low intertidal and subtidal (to 20 m depth) on rocks, dead coral fragments often covered with silt in sheltered sites.

Africa, Indian Ocean Islands. Common in countries of the Asia-Pacific Region: China, Japan, Taiwan, Vietnam, Thailand, Indonesia, Malaysia, Singapore, Philippines, Australia, New Zealand, Pacific Islands.