Silvetia babingtonii

Thallus bushy, leathery, 15–20(–50) cm high, dark olive or yellowish-brown. Stipe almost cylindrical, short. Branching repeatedly dichotomous, in one plane. Branches cylindrical at the lower part, compressed at the upper part, 0.15-0.4 (-0.8) cm wide, without midrib. Air bladders oblong-oval, often bifurcated (protruding from both sides of branches) are developed on the branches, often in diverging point. Receptacles 3-4 cm long, broadly-linear, with forked top and swollen base, are developed at the tips of branches. Attachment by discoid holdfast. Growing in the upper intertidal zone, intertidal pools and in the upper subtidal zone up to 5 m on rocky bottom, in semisheltered and open coastal areas.

Asia: Japan, Korea and Russia (the Sea of Japan, the Sea of Okhotsk).