This species of brown seaweed looks like a flattened cactus.  A flat main axis aprox. 2 cm wide with obvious midrib arises from a discoid holdfast.  Numerous thinner opposite growing flat side branches are attached to the main axis. D. ligulata grows low to subtidal and reaches 80 cm in length.  Other species of flattened Desmarestia have been described for our area and there is ongoing discussion about the relationships of these species and their exact number.  D. munda is described as growing to over 120 cm with side branches as wide as the main axis (4-10 cm.), but strictly subtidal.  Beach Watchers have observed individuals that match both descriptions or a combination of the two.

Link for (Pereira, 2010) Handbook Guide

Original publication: Lamouroux, J.V.F. (1813). Essai sur les genres de la famille des thalassiophytes non articulées. Annales du Muséum d'Histoire Naturelle, Paris 20: 21-47, 115-139, 267-293, Plates 7-13.

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Adjective (Latin), ligulate (Stearn 1973)

Nomenclatural notes: M.J. Wynne commented (e-mail. August 2006) "...in regard to Gmelin's name of 1768, a species described from the Mediterranean. So nom. illeg. should be added after Fucus ligulatus Lightfoot Herbacea ligulata. Stackhouse (1809) salvaged the epithet, and thus the authorship is now: Desmarestia ligulata (Stackhouse) J.V. Lamouroux." - (17 Aug 2006) - Wendy Guiry

Source of hydrocolloids - source of laminaran.

The brown algae Desmarestia ligulata, and D. viridis accumulate Sulphuric Acid until their average internal pH is 0.5 to 0.8. A related species, D. aculeata, does not accumulate acid (McClintock et al. 1982)

Fletcher, R.L. (1987). Seaweeds of the British Isles. Vol. 3. Fucophyceae (Phaeophyceae). Part 1. pp. i-x, 1359, 90 figs, 15 pls. London: British Museum (Natural History).

Lindeberg, M.R. & Lindstrom, S.C. (2010). Field guide to the seaweeds of Alaska. pp. [i-]iii-iv, 1-188, numerous col. photographs. Fairbanks: Alaska Sea Grant College Program.

Loiseaux-de Goër, S. & Noailles, M.-C. (2008). Algues de Roscoff. pp. [1]-215, col. figs. Roscoff: Editions de la Station Biologique de Roscoff.

Mondragon, J. & Mondragon, J. (2003). Seaweeds of the Pacific Coast. Common marine algae from Alaska to Baja California. pp. iv, 5-97. Monterey, California: Sea Challengers.

Papenfuss, G.F. (1964). Catalogue and bibliography of Antarctic and Sub-Antarctic benthic marine algae. In: Bibliography of the Antarctic Seas. (Lee, M.O. Eds) Vol.1, pp. 1-76. Washington D.C.: American Geophysical Union.

Stegenga, H., Karremans, M. & Simons, J. (2007). Zeewieren van de voormalige oesterputten bij Yerseke. Gorteria 32: 125-143.

Womersley, H.B.S. (1987). The marine benthic flora of southern Australia. Part II. pp. 481, 169 figs, 1 table, 8 plates, 4 maps. Adelaide: South Australian Government Printing Division.

Basionym: Herbacea ligulata Stackhouse