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]