Brown Algae


Brown algae form a natural class, the Phaeophyceae, including c. 265 genera with 1500–2000 species. They form rich underwater forests along much of the cold and temperate coastlines of our planet.

Keywords: Algae; Dictyotales; Ectocarpales; Fucales; Laminariales; Phaeophyceae; seaweed

Figure 1.

Morphological diversity among brown algae. (a) Epilithic carpet of intertidal brown algae. (b) Pilayella littoralis: filamentous brown (scale 1 cm). (c) Ralfsia fungiformis: crustose representative (scale 2 cm). (d) Laminaria saccharina: a kelp (scale 10 cm). (e) Alaria nana: a kelp with sporophylls (ruler in cm). (f) Postelsia palmaeformis: a member of the Lessoniaceae (scale 11 cm). (g) Macrocystis integrifolia: a giant kelp; inserts (left to right) holdfast, sporophyll, region of blade production. (h) Hormosira banksii: a southern hemisphere fucoid (scale 3 cm). (i) F. spiralis: a high intertidal fucoid (scale 3 cm). (j) F. distichus ssp. edentatus: a low intertidal inhabitant (scale 2.5 cm) with a close‐up (k) of developing receptacles and their characteristic conceptacles (scale 1 cm). The author graciously acknowledges the assistance of Mr Roger Smith (University of New Brunswick) in production of this figure.

Figure 2.

Schematic diagram of vegetative cell anatomy. CW, cell wall; PM, plasma membrane; PL, plasmodesmata; NU, nucleus; N, nucleolus; NER, nuclear endoplasmic reticulum; ER, endoplasmic reticulum; M, mitochondria; GO, Golgi body; CH, discoid plastid; CER, chloroplast endoplasmic reticulum; CE, chloroplast envelope; PER, periplastidial endoplasmic reticulum; T, thylakoid; G, gonophore; PY, pyrenoid; CV, cytoplasmic vacuole; PH, physode. The anatomy of one plastid (CH*) was not elaborated. Based on information from van den Hoek et al..

Figure 3.

Common life history types. (a) Isomorphic pattern typical of some Ectocarpales. (b) Heteromorphic pattern of the Laminariales. See text for details. R!, meiosis.



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Further Reading

Bold HC and Wynne MJ (1985) Introduction to the Algae:Structure and Reproduction, 2nd edn. Englewood Cliffs, NJ: Prentice‐Hall.

Clayton MN (1988) Evolution and life histories of brown algae. Botanica Marina 31: 379–387.

De Reviers B and Rousseau F (1999) Towards a new classification of the brown algae. Progress in Phycological Research 13: 107–201.

Fletcher RL (1987) Seaweeds of the British Isles, Vol. 3: Fucophyceae (Phaeophyceae), part 1. London: British Museum (Natural History).

Lobban CS and Harrison PJ (1997) Seaweed Ecology and Physiology. Cambridge: Cambridge University Press.

Lüning K (1990) Seaweeds. Their Environment, Biogeography, and Ecophysiology. New York: Wiley.

Womersley HBS (1987) The Marine Benthic Flora of Southern Australia, Part II. Adelaide: South Australian Government Printing Division.

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How to Cite close
Lane, Christopher E, and Saunders, Gary W(Apr 2006) Brown Algae. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0004250]