Pelvetia canaliculata
| Pelvetia canaliculata | |
|---|---|
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| Scientific classification | |
| Kingdom: | Chromalveolata |
| Division: | Heterokontophyta |
| Class: | Phaeophyta |
| Order: | Fucales |
| Family: | Fucaceae |
| Genus: | Pelvetia |
| Species: | P. canaliculata |
| Binomial name | |
| Pelvetia canaliculata (L.) Decne. & Thur. |
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Pelvetia canaliculata, channelled wrack, is a very common brown alga (Phaeophyceae) found on the rocks of the upper shores of Europe.
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[edit] Description
Pelvetia grows to a maximum length of 15 centimetres (6 in) in dense tufts, the fronds being deeply channelled on one side: the channels and a mucus layer help prevent the seaweed drying when the tide is out. It is irregularly dichotomously branched with terminal receptacles,[1] and is dark brown in colour. 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-vesicules and forms the uppermost zone of algae on the shore growing at or above high water mark.[2] The reproductive organs form swollen, irregularly shaped receptacles at the end of the branches. The conceptacles are hermaphrodite and borne within the receptacles.
[edit] Ecology and distribution
P. 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.[3] 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.[4]
[edit] Distribution
Pelvetia canaliculata is common on the Atlantic shores of Europe from Iceland to Spain, including Norway, Ireland, Great Britain, the Netherlands, France and Portugal.[5] In Ireland, collection of Pelvetia canaliculata (Irish: dúlamán) has been recorded as a source of sustenance during times of famine.[6] A popular Irish folk song, Dúlamán, describes events transpiring between two people who collected the seaweed as a profession.
[edit] References
- ^ L. Newton (1931). A Handbook of the British Seaweeds. British Museum, London.
- ^ C. I. Dickinson (1963). British Seaweeds. The Kew Series.
- ^ J. R. Lewis (1964). The Ecology of the Rocky Shores. The English Universities Press Ltd. London.
- ^ D. Thomas (2002). Seaweeds. Life Series. Natural History Museum, London. ISBN 0-565-09175-1.
- ^ M. D. Guiry & Wendy Guiry (October 25, 2006). "Pelvetia canaliculata (Linnaeus) Decaisne & Thuret". AlgaeBase. http://www.algaebase.org/speciesdetail.lasso?species_id=88&sk=0&from=results.
- ^ Doreen McBride, When Hunger Stalked the North (1994).
[edit] External links
- N. White (2006). "Channelled wrack, Pelvetia canaliculata". Marine Life Information Network for Britain and Ireland. Plymouth: Marine Biological Association of the United Kingdom. http://www.marlin.ac.uk/species/Pelvetiacanaliculata.htm.
- David W. Connor, James H. Allen, Neil Golding, Kerry L. Howell, Louise M. Lieberknecht, Kate O. Northern & Johnny B. Reker (2004). "LR.LLR.F.Pel: Pelvetia canaliculata on sheltered littoral fringe rock". The Marine Habitat Classification for Britain and Ireland Version 04.05. JNCC, Peterborough. ISBN 1-861-07561-8. http://www.jncc.gov.uk/Marine/biotopes/biotope.aspx?biotope=JNCCMNCR00000637.
- British Isles Seaweeds Images
