Limu (algae)

Limu, otherwise known as rimu, remu or ʻimu (from Proto-Austronesian *limut)^[1] is a general Polynesian term for edible plants living underwater, such as seaweed, or plants living near water, like algae.^[2][3] In Hawaii, there are approximately one hundred names for kinds of limu, sixty of which can be matched with scientific names.^[4] Hundreds of species of marine algae were once found in Hawaii.^[5] Many limu are edible, and used in the cuisine throughout most of Polynesia.

Ahi limu poke: raw fish with limu

Uses

Several species of limu are used as food throughout Polynesia and is typically eaten raw as accompaniment to meals, usually fish.

In Hawaii, limu was seen as a major component of the Hawaiian diet alongside fish and poi.^[6] Hawaiians cultivated several varieties of seaweed for food as well as to feed fish farmed within fish ponds. As many as 75 types of limu were used for food, more than the 35 used in Japanese cuisine, which is also well known for its use of seaweed.^[5] In modern times, limu is often used as a condiment, typically in raw fish dishes such as poke.^[7]

Limu was used in hoʻoponopono, the ancient Hawaiian process of conflict resolution. Injured and accused parties gathered to pray, seek forgiveness and eat limu kala leaves as a symbol of reconciliation.^[7][8] It is also used in traditional hula attire^[9] and as medicine.^[10]

Due to the shape of its foliage, the Maori also applied the name rimu to the native tree Dacrydium cupressinum.^[2]

Types

Limu comes from multiple genera^[6]

Cook Islands

Image	English name	Indigenous name	Description and use
	Crowned sea bells (Turbinaria ornata)	Remu taratara (Rarotonga and Mauke), Rimu taratara (Aitutaki), Limu (Pukapuka)[11]
	Double-edge sargassum (Sargassum aquifolium)	Rimu akau[12]
	Open-sponge seaweed (Hydroclathrus clathratus)	Remu oma (Rarotonga)[13]
	Sargassum obtusifolium (Sargassum obtusifolium)	Remu ʻūmoemoe (Rarotonga)[14]
	Sea grapes (Caulerpa racemosa)	Remu kai (Rarotonga and Mauke), Remu kōnini (Mangaia), Rimu kai (Aitutaki)[15]
	Turkeytail seaweed (Padina boryana)	Remu taʻiriʻiri (Rarotonga)[16]

Easter Island

Image	English name	Indigenous name	Description and use
	Dictyopteris australis (Dictyopteris australis)	Auke
	Sargassum obtusifolium (Sargassum obtusifolium)	Miritoni

French Polynesia

Image	English name	Indigenous name	Description and use
	Cactus tree alga (Caulerpa cupressoides)	Mamaʻga (Rapan)	[17]
	Chnoospora minima (Chnoospora minima)	Imu keikei aoa (Marquesan)	[18]
	Cladophora patentiramea (Cladophora patentiramea)	Imu ouoho (Marquesan)	[18]
	Gracilaria (Gracilaria)	Remu ʻura (Tahitian)
	Grass kelp (Enteromorpha flexuosa)	Imu vai (Marquesan)	[18]
	Green sea cushion (Codium arabicum)	Imu tutae kioe (Marquesan)	[18]
	Sea grapes (Caulerpa racemosa)	ʻonini (Tahitian), Imu topua (Marquesan), Remu vine (Austral), Konini (Rapan)	[18]
	Sea lettuce (Ulva lactuca)	Rimu miti (Tahitian), Imu kokuu (Marquesan)	[18]

Hawaii

Image	English name	Indigenous name	Description and use
	Antler seaweed (Codium reediae)	Limu aʻalaʻula
	Branched sea cushion (Codium edule)	Limu wawaeʻiole	Meaning "rat's foot seaweed"
	Branched string lettuce (Ulva prolifera)	Limu ʻeleʻele
	Champia (Champia)	Limu ʻoʻolu	Meaning "thin seaweed". Shares its name to the similarly used species Chondria tenuissima.
	Chondria tenuissima (Chondria tenuissima)	Limu ʻoʻolu	Meaning "thin seaweed". Shares its name to the similarly used Champia seaweeds.
	Chylocladia (Chylocladia)	Limu akuila, Limu kihe
	Crowned sea bells (Turbinaria ornata)	Limu kahili
	Dictyopteris (Dictyopteris)	Limu lipoa	Meaning "seaweed gathered from the deep" referring to its habitat of growing in deep water. The species Dictyopteris australis and Dictyopteris plagiogramma were gathered as food.
	Dictyota (Dictyota)	Limu alani	Meaning "bitter seaweed"
	Double-edge sargassum (Sargassum aquifolium)	Limu kala	Meaning "forgiving seaweed" employed during hoʻoponopono.
	Grateloupia filicina (Grateloupia filicina)	Limu huluhuluwaena	or "pubic hair") – favorite of Liliʻuokalani.[8]
	Gelidium (Gelidium)	Limu loloa	Meaning "long or slender seaweed"[5]
	Griffithsia (Griffithsia)	Moʻopunaakalīpoa, Moʻopuna
	Gymnogongrus (Gymnogongrus)	Limu koele	Meaning "dry or hard seaweed"[5]
	Halymenia formosa (Halymenia formosa)	Lepelepe-o-Hina	shawl of the goddess Hina. Shares its name with a native butterfly and a family of nudibranchs.[8]
	Laurencia nidifica (Laurencia nidifica)	Limu maneʻoneʻo
	Laver (Porphyra)	Limu luau, Lipaheʻe
	Martensia fragilis (Martensia fragilis)	Limu haʻula
	Ogo (Gracilaria coronopifolia)	Limu manauea	cooked with meats to form a savory jelly. Later diced raw with poke, mixed with chili and salt.[8]
	Polysiphonia (Polysiphonia)	Limu hāwane
	Red sea plume (Asparagopsis taxiformis)	Limu kohu	Meaning "supreme seaweed"
	Sailor’s eye (Valonia utricularis)	Limu lipuʻupuʻu
	Sea lettuce (Ulva lactuca)	Limu palahalaha, Pakaiea	named after a shark god who was swaddled in its silken leaves.[8][19] used in hula[20]
	Spyridia spinella (Spyridia spinella)	Limu hulu puaʻa
	Tattered sea moss (Hypnea)	Limu hina
	Tuffed seaweed (Ahnfeltiopsis concinna)	Limu ʻakiʻaki

New Zealand

Image	English name	Indigenous name	Description and use
	Bubble caulerpa (Caulerpa sedoides)	Rimurimu
	Carrageenan weed (Gigartina)	Rehia, Rimurehia
	Clymene (Clymene)	Karengo, Kareko, Parengo, Reporepo
	Eelgrass (Zostera)	Karepō, Nana
	Gracilaria (Gracilaria)
	Kelp (Laminariales)	Pakake, Pakaka
	Laver (Porphyra)	Karengo, Kareko, Parengo, Reporepo	Originally, Karengo was used to describe seaweed belonging to the Porphyra genus. Recent genomic analysis however has Karengo cover more than 30 species belonging to genus Porphyra, Pyropia, Clymene and Lysithea.
	Lysithea (Lysithea)	Karengo, Kareko, Parengo, Reporepo
	Neptune’s necklace (Hormosira banksii)	Koiri
	Sea lettuce (Ulva lactuca)	Rimu kaikai
	Sea rimu (Caulerpa brownii)	Rimurimu
	Southern bull kelp (Durvillaea)	Rimurapa, Rimuroa, Kōauau
	Southern laver (Pyropia)	Karengo, Kareko, Parengo, Reporepo

Niue

Image	English name	Indigenous name	Description and use
	Cactus tree alga (Caulerpa cupressoides)	Limu tahi
	Sea grapes (Caulerpa racemosa)	Limu fua

Samoa

Image	English name	Indigenous name	Description and use
	Crowned sea bells (Turbinaria ornata)	Limu lautalatala
	Gracilaria (Gracilaria)	Limu aau
	Halymenia (Halymenia)	A ʻau
	Sargassum (Sargassum)	Limu vavoa
	Sea grapes (Caulerpa racemosa)	Fuafua
	Turkeytail seaweed (Padina boryana)	Limu lautaliga

Tonga

Image	English name	Indigenous name	Description and use
	Cactus tree alga (Caulerpa cupressoides)	Kaka	[21]
	Cladosiphon (Cladosiphon)	Tangaʻu	[21]
	Flat-top sea grape (Caulerpa peltata)	Fuofua	[21]
	Green feather algae (Caulerpa sertularioides)	Louniu, Louango, Tuʻaniu	[21]
	Hypnea charoides (Hypnea charoides)	Limu vai	[21]
	Scalpel green seaweed (Caulerpa scalpelliformis)	Palalafa	[21]
	Sea grapes (Caulerpa racemosa)	Toke, Fuofua, Alako, Teʻemoa, Teʻepuaka	[21]
	Serrated green seaweed (Caulerpa serrulata)	Kaka	[21]

Tuvalu

Image	English name	Indigenous name	Description and use
	Sea grapes (Caulerpa racemosa)	Limu pukupuku

Threats

Limu has become increasingly difficult to find because of over-picking, pollution, and urban development,^[22] especially construction in watersheds. Many important kinds of limu grow best in brackish water where fresh water empties into the sea. Another threat to limu is the spread of marine alien invasive species, such as members of the genus Kappaphycus (smothering seaweed), Gracilaria salicornia (gorilla ogo), Avrainvillea amadelpha (leather mudweed), Hypnea musciformis (hook weed) and Acanthophora spicifera (prickly seaweed).^[23]

See also

• Edible seaweed
• Oceanic cuisine

Further reading

• Abbott, Isabella Aiona (1992). Lā'au Hawai'i: Traditional Hawaiian Uses of Plants. Bishop Museum Press. ISBN 9780930897628.
• Abbott, Isabella Aiona; Huisman, John Marinus (2004). Marine Green and Brown Algae of the Hawaiian Islands. Bishop Museum Press. ISBN 9781581780307.