Authority: (Delile) Trevisan
Hawaiian name: limu kohu ('supreme')
Characteristic feature: Fluffy appearance, and shaped like a Christmas tree.
Description: Gametophytes 10-20 cm tall, with several to many erect, generally plumose fronds, plumose portions to 3 cm diam., lower axes usually naked, to 2 mm diam., branching starting at lower fourth or third of each axis; dark rose to dark red unless subjected to intertidal exposure. Tetrasporangial phase uncommon in intertidal or shallow subtidal habitats but common as epiphyte on large number of other algae from 4-60 m depths.
Habitat: Intertidal to shallow subtidal; in areas of constant water motion.
Hawaiian distribution: All main Hawaiian Islands including the Northwestern Hawaiian Islands.
Other: A favourite limu of most Hawaiians. Small quantities are used in food as the flavour is strong, bitter, and penetrating. Traditionally, the limu is soaked overnight in fresh water to reduce the bitter iodine flavour. Collect only the upright stems, leaving the base to grow new stems. In ancient Hawaiian civilization this limu was forbidden to all but the ali‘i (royalty).