Pelvetia | |
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Close-up | |
Growing on the side of a slipway | |
Scientific classification | |
Domain: | Eukaryota |
Clade: | Diaphoretickes |
Clade: | SAR |
Clade: | Stramenopiles |
Phylum: | Gyrista |
Subphylum: | Ochrophytina |
Class: | Phaeophyceae |
Order: | Fucales |
Family: | Fucaceae |
Genus: | Pelvetia Decne. & Thur. |
Species: | P. canaliculata |
Binomial name | |
Pelvetia canaliculata | |
Synonyms [1] | |
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Pelvetia canaliculata, the channelled wrack, [2] is a very common brown alga (Phaeophyceae) found on the rocks of the upper shores of Europe. It is the only species remaining in the monotypic genus Pelvetia. [1] [3] In 1999, the other members of this genus were reclassified as Silvetia due to differences of oogonium structure and of nucleic acid sequences of the rDNA. [4]
Pelvetia grows to a maximum length of 15 centimetres (6 in) in dense tufts, the fronds being deeply channeled on one side: the channels and a mucus layer help prevent the seaweed drying (desiccation) when the tide is out. It is irregularly dichotomously branched [5] with terminal receptacles, [6] and is dark brown in color. Each branch is of uniform width and without a midrib. The receptacles are forked at the tips.
It is distinguished from other large brown algae by the channels along the frond. It has no mid-rib, no air-vesicles and no cryptostomata. It forms the uppermost zone of algae on the shore growing at or above high-water mark. [7] The reproductive organs form swollen, irregularly shaped receptacles at the end of the branches. The conceptacles are hermaphrodite and borne within the receptacles at the apices.
The genus name of Pelvetia is in honour of François Alexandre Pelvet (1801–1882), who was a French naturalist and plant collector. [8]
The genus was circumscribed by Joseph Decaisne and Gustave Adolphe Thuret in Ann. Sci. Nat. Bot. ser. 3, vol. 3 on page 12 in 1845.
Both sexes occur in the same plant, the reproductive structures develop at the apices. [9] The receptacles are swollen during the summer and are yellowish-green at maturity. [10]
Pelvetia canaliculata is the only large algae growing on rocks forming a zone along the upper shore at the upper littoral zone, on the shores of the British Isles. It tolerates a wide range of exposure conditions. [11] It needs periods of exposure to the air, and sometimes grows so high up a beach that coarse grass and other longshore angiosperms grow among it. If it is submerged for more than six hours out of 12 it begins to decay. [12]
Pelvetia canaliculata is common on the Atlantic shores of Europe from Iceland to Spain, including Norway, Ireland, Great Britain, the Netherlands, France and Portugal. [13] In Ireland, collection of Pelvetia canaliculata (Irish : dúlamán) has been recorded as a source of sustenance during times of famine. [14] A popular Irish folk song, Dúlamán , describes events transpiring between two people who collected the seaweed as a profession.[ citation needed ]
Fucus vesiculosus, known by the common names bladderwrack, black tang, rockweed, sea grapes, bladder fucus, sea oak, cut weed, dyers fucus, red fucus and rock wrack, is a seaweed found on the coasts of the North Sea, the western Baltic Sea and the Atlantic and Pacific Oceans. It was the original source of iodine, discovered in 1811, and was used extensively to treat goitre, a swelling of the thyroid gland related to iodine deficiency.
Fucus is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world.
Ascophyllum nodosum is a large, common cold water seaweed or brown alga (Phaeophyceae) in the family Fucaceae. Its common names include knotted wrack, egg wrack, feamainn bhuí, rockweed, knotted kelp and Norwegian kelp. It grows only in the northern Atlantic Ocean, along the north-western coast of Europe including east Greenland and the north-eastern coast of North America. Its range further south of these latitudes is limited by warmer ocean waters. It dominates the intertidal zone. Ascophyllum nodosum has been used numerous times in scientific research and has even been found to benefit humans through consumption.
Alaria esculenta is an edible seaweed, also known as dabberlocks or badderlocks, or winged kelp, and occasionally as Atlantic Wakame. It is a traditional food along the coasts of the far north Atlantic Ocean. It may be eaten fresh or cooked in Greenland, Iceland, Scotland and Ireland. It is the only one of twelve species of Alaria to occur in both Ireland and in Great Britain.
The Fucaceae are a family of brown algae, containing six genera:
Fucus serratus is a seaweed of the north Atlantic Ocean, known as toothed wrack, serrated wrack, or saw rack.
Fucus spiralis is a species of seaweed, a brown alga, living on the littoral shore of the Atlantic coasts of Europe and North America. It has the common names of spiral wrack and flat wrack.
Leathesia marina (Lyngbye) Decaisne, 1842, previously known as Leathesia difformis Areschoug, 1847, commonly known as the sea cauliflower the sea potato, and brown brains is a species of littoral brown algae in the class Phaeophyceae and the order Ectocarpales, which is commonly attached to other seaweeds and sometimes rocks. When young, the organism is solid but as it matures it becomes hollow and somewhat convoluted and has the appearance of a small leathery brown bag about the same size as a tennis ball. The texture is rubbery and the outer surface smooth.
Corallina officinalis is a calcareous red seaweed which grows in the lower and mid-littoral zones on rocky shores.
Osmundea pinnatifida is a species of red alga known by the common name pepper dulse.
Fucus distichus or rockweed is a species of brown alga in the family Fucaceae to be found in the intertidal zones of rocky seashores in the Northern Hemisphere, mostly in rock pools.
Gongolaria baccata is a species of brown seaweed in the family Fucaceae. It is found in the north east Atlantic, the Baltic Sea and the Mediterranean Sea. The species name baccata means "berry-like" and refers to the small air bladders.
Chorda filum, commonly known as dead man's rope or sea lace among other names, is a species of brown algae in the genus Chorda. It is widespread in the temperate waters of the northern hemisphere. The species has numerous other common names related to its physical appearance. These include mermaid's tresses, cat's gut or sea-catgut, bootlace weed, sea-twine, and mermaid's fishing line.
Silvetia is a genus of brown algae, commonly known as rockweed, found in the intertidal zone of rocky seashores of the Pacific Ocean. These were originally classified as members of the genus Pelvetia. In 1999, Silvetia sp. was created as a separate species from Pelvetia canaliculata due to differences of oogonium structure and of nucleic acid sequences of the rDNA. It was renamed in honor of Paul Silva, Curator of Algae at the Herbarium of the University of California, Berkeley. There are three species and one subspecies.
Fucus guiryi is a brown alga in the family Fucaceae. It is known from numerous locations along the east coast of the North Atlantic Ocean, from Ireland to the Canary Islands.
Fucus ceranoides is a species of brown algae found in the littoral zone of the sea shore.
Hypoglossum hypoglossoides, known as under tongue weed, is a small red marine alga in the family Delesseriaceae.
Phycodrys rubens is a red marine alga of up to 30 cm long.
Phyllophora pseudoceranoides, the stalked leaf bearer, is a small marine red alga.
Odonthalia dentata is a medium-sized marine red alga.