Bryopsis ryukyuensis

Thallus soft, lubricous, dark green, with bluish iridescence, forming a very dense caespitose tufts, to 18 cm high. Main axes 0.4–0.6 mm diam. in middle part, to 1 mm diam. at the basal portion of the main axes, naked below (1/2–1/3 of the axes), branching above. Branches to three orders, few in number. Branchlets (pinnulae) with obtuse apices, cylindrical, (20–)30–50 mm diam., to 1.2 mm long, develop from all sides of branches, constricted at base, decreasing in length (to 100 mm long or less), towards apices at upper portion, hair-like in the upper portion. Attachment by branched, slender, entangled, often inflated rhizoids. Growing in crevices, pools, on rocks, dead corals in the lower intertidal zones to upper subtidal at shores exposed to moderate wave action.

Subtropics, tropics of Western Atlantic, Japan (Ryukyu Archipelago), Korea.