Lomentaria catenata

Thallus slightly cartilaginous, filamentous, bushy, arising from creeping stolons, 6-20 cm high, deep pink, to purple-red, hollow,cylindrical, 1-1.5(-2) mm in diam. Branching bi- tripinnate, with branches arranged sparsely (at distance) oppositely, closely alternately or fasciculate. Ultimate branchlets arranged sparsely opposite or verticillate. The branchlets catenate due to constrictions at intervals, in series by 3-4 fusiform or ellipsoidal inflations. Sporangia in sori, immersed in branchlets, oval, roundish in surface view, 50-100 μm diam., tetrahedrally, irregularly tetrahedrally divided, develop in swollen ultimate branchlets. Cystocarps prominent, spherical, 950-1200 μm diam. Growing in rocky tide pools, in the lower intertidal and upper subtidal zones.

Countries of the Asia-Pacific Region.