Spiral wrack (Fucus spiralis)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Chromista · Phylum: Ochrophyta · Class: Phaeophyceae · Order: Fucales · Family: Fucaceae · Genus: Fucus.

Accepted name: Fucus spiralis · Authority: Linnaeus, 1753 · Taxonomic status: accepted · AphiaID: 145547.

Synonyms and superseded combinations recorded for this taxon: Fucus areschougii Kjellman, 1890; Fucus areschougii f. nanus Kjellman, 1890; Fucus areschougii var. borealis (Kjellman) Kjellman, 1890; Fucus platycarpus f. spiralis (Linnaeus) Thuret, 1878; Fucus platycarpus var. spiralis (Linnaeus) Rosenvinge, 1897; Fucus sherardii f. spiralis (Linnaeus) Areschoug, 1868; Fucus spiralis f. arenicola Hamel, 1939; Fucus spiralis f. borealis Kjellman, 1883; Fucus spiralis f. nanus (Kjellman) Batters, 1902; Fucus spiralis var. nanus (Kjellman) S.M.Baker & Bohling, 1916; Fucus spiralis var. nanus (Stackhouse) Batters, 1902; Fucus spiralis var. typicus Børgesen, 1902; Fucus vesiculosus f. spiralis (Linnaeus) Batters, 1890; Fucus vesiculosus var. spiralis (Linnaeus) C.Agardh, 1810; Fucus vesiculosus var. spiralis (Linnaeus) Roth, 1800; Halidrys spiralis (Linnaeus) Stackhouse, 1809.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=145547 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (SeaLifeBase)

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

Habitat zone: sessile.

Source: SeaLifeBase species summary (SpecCode 127366) — https://www.sealifebase.se/summary/Fucus-spiralis.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

19,994 georeferenced occurrence records for Fucus spiralis are published through GBIF from 29 countries or marine areas. The map above plots 181 distinct locations from a sample of 3,000 records, omitting 292 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 Kingdom of Great Britain and Northern Ireland (6,619); France (3,246); Norway (1,783); Netherlands (1,717); Canada (1,633).

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

Source: GBIF Occurrence Search (taxonKey 3196369) — https://www.gbif.org/occurrence/search?taxon_key=3196369&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=145547 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Description and natural history (Wikipedia)

Fucus spiralis is olive brown in colour and similar to Fucus vesiculosus and Fucus serratus. It grows to about 30 cm long and branches somewhat irregularly dichotomous and is attached, generally to rock, by a discoid holdfast. The flattened blade has a distinct mid-rib and is usually spirally twisted without a serrated edge, as in Fucus serratus, and it does not show air-vesicles, as Fucus vesiculosus.

The reproductive bodies form rounded swollen tips on the branches, usually in pairs.

In the conceptacles oögonia and antheridia are produced after meiosis and then released. Fertilisation follows and the zygote develops directly into the diploid sporophyte plant.

The other common species of Fucus on the coasts of British Isles: Fucus spiralis, Fucus vesiculosus and Fucus serratus along with Ascophyllum nodosum form the main and dominant seaweeds on rocky shores. These three species, along with two others Pelvetia canaliculata and Ascophyllum nodosum form the zones along the shore.

F. spiralis is common on the coasts all around the British Isles, western coasts of Europe, Canary Islands and North-eastern America.

Fucus spiralis produces phlorotannins of both the fucol and fucophlorethol types.

Source: Wikipedia: Fucus spiralis — https://en.wikipedia.org/wiki/Fucus_spiralis (CC BY-SA 4.0). Accessed 2026-09-23.