( Cystoseira crinita )

/ / Marine Flora

Cystoseira crinita has an upright, bushy thallus with smooth axes; it reaches a height of 50-350mm, and a width of 200-500mm (1; 2). The main branches are rough, thin and alternate; the upper section is particularly densely branched (1).The secondary ramifications are lacking spines, and the terminal receptacle are long, and compact (1). This alga lacks tophules and the gas vacuoles are either missing or few (1). C. crinita has a light-brown to blackish colouration.

There are approximately 58 species within the genus Cystoseira (3); none of the species are listed under the IUCN Redlist (4); however, C. amentacea, C. mediterranea, C. sedoides, C. spinose and C. zosteroides are all listed under Appendix I of the BERN Convention (5).


C. crinita has a moderate tolerance to wave energy (1).


C. crinita is located in the upper infra-littoral zone in moderately exposed sites; they prefer well-lit areas in 0-1.5m on rocky substrates (1).

Life Cycle

C. crinita is an annual species (1).


C. crinita is located in the Mediterranean and the north-east Atlantic (1).


C. crinita uses photosynthesis, as well as requiring various inorganic nutrients, such as carbon dioxide, phosphorus and fixed nitrogen (2).

Conservation Status

Not listed under the IUCN Redlist (4).


Description written by Ben Harvey (2009)

(1)   Cabioc’H, J., Floc’H, J. & Le Toquin, A., 1992. Guide mes algues des mers d’Europe. Paris: Delachaux et Niestle.

(2)   Graham, L.E. & Wilcox, L.W., 2000. Algae. New Jersey: Prentice-Hall Inc.

(3)   Guiry, M.D. (2009). Cystoseira C. Agardh, 1820. In: Guiry, M.D. & Guiry, G.M. (2009). AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Accessed through the World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=144126 on 2009-09-02

(4)   IUCN, 2009. IUCN Red List of Threatened Species. [Online] (2009.1) Available at: www.iucnredlist.org [Accessed 01 September 2009].

(5)   Europe, C.o., 2002. Convention on the conservation of European wildlife and natural habitats: Bern Convention. [Online] Available at: http://conventions.coe.int/Treaty/FR/Treaties/Html/104-1.htm [Accessed 02 September 2009].