Winding nori (Ulva flexuosa)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Plantae · Phylum: Chlorophyta · Class: Ulvophyceae · Order: Ulvales · Family: Ulvaceae · Genus: Ulva.

Accepted name: Ulva flexuosa · Authority: Wulfen, 1803 · Taxonomic status: accepted · AphiaID: 234468.

Synonyms and superseded combinations recorded for this taxon: Conferva flexuosa Roth, 1800; Enteromorpha compressa var. lingulata (J.Agardh) Hauck, 1884; Enteromorpha flexuosa (Wulfen) J.Agardh, 1883; Enteromorpha intestinalis f. tubulosa (Kützing) V.J.Chapman, 1937; Enteromorpha intestinalis var. tubulosa Kützing, 1845; Enteromorpha lingulata J.Agardh, 1883; Enteromorpha prolifera var. tubulosa (Kützing) Batters, 1902; Enteromorpha tubulosa (Kützing) Kützing, 1856; Enteromorpha tubulosa var. ramosa Schiffner.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=234468 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (SeaLifeBase)

Measured values published by SeaLifeBase for Ulva flexuosa. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Maximum length: 20 cm · Habitat zone: epiphytic · Vulnerability index: 10 of 100.

SeaLifeBase notes: Fronds are up to 20 cm in height. This is used as bait in fish traps (Ref. 801). Occurs in shallow intertidal mangrove prop roots and wood, or epiphytic in brackish water of estuaries (Ref. 83908). Also on subtidal volcanic rocks (Ref. 80999).

Source: SeaLifeBase species summary (SpecCode 116907) — https://www.sealifebase.se/summary/Ulva-flexuosa.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

2,921 georeferenced occurrence records for Ulva flexuosa are published through GBIF from 97 countries or marine areas. The map above plots 314 distinct locations from a sample of 2,921 records, omitting 405 inland records that carry an institution's coordinates rather than a collection site; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: United States of America (762); Mexico (293); Brazil (292); United Kingdom of Great Britain and Northern Ireland (214); Sweden (195).

The full country table, WoRMS marine regions and the sampling notes are on this species' Distribution page.

Source: GBIF Occurrence Search (taxonKey 5273507) — https://www.gbif.org/occurrence/search?taxon_key=5273507&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=234468 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Description and natural history (Wikipedia)

This large green alga may grow to 25 cm, it is tubular and similar to E. prolifera. It is very variable with branches showing cells in longitudinal and sometimes also in transverse rows.

The species can be found in such European countries as Ireland, Belgium, Bulgaria, France, Greece, Italy, Portugal, Romania, Slovenia, Spain, Sweden, Great Britain (Scotland), and on island of Corsica.

In Africa it can be found in Algeria, Cameroon, Egypt, Gabon, Guinea, Equatorial Guinea, Eritrea, Ethiopia, Liberia, Namibia, Nigeria, Senegal, Sierra Leone, Somalia, South Africa, Togo, Tunisia, and on the islands such as Canary Islands, Madagascar, Mauritius and São Tomé and Príncipe.

In Asia, it is found in Bahrain, China, India, Iran, Kuwait, Pakistan, Saudi Arabia, Taiwan and Yemen.

It is also have North and South American distribution, which includes countries such as Argentina, Brazil, Chile, Ecuador, Mexico, Uruguay and Venezuela. In Central America it can be found in such countries as Belize, Costa Rica, and Panama, while in Caribbean it can be found on Bahamas, Barbados, Cuba, Hispaniola, Jamaica, Martinique, Tobago, Virgin Islands, and on Lesser and Netherlands Antilles.

The species is distributed throughout the US states such as California, Florida, Mississippi, North Carolina, Oregon, Texas, and Washington.

Source: Wikipedia: Ulva flexuosa — https://en.wikipedia.org/wiki/Ulva_flexuosa (CC BY-SA 4.0). Accessed 2026-09-23.

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