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Name derivation:

Mastocarpus = L. masto: nipple like + carpus: fruit

stellatus = L. stellatus: star like

Common names: breast fruit alga, caragheen moss, false carrageen moss, and Turkish washcloth

"Breast fruit" alga



Mastocarpus Ktzing 1843; 14 of 26 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014).

Order Gigartinales; Family Phyllophoraceae



Two types of life histories are known in Mastocarpus stellatus, an apomictic one in which gametophytic blades are recycled (Chen et al. 1974; Edelstein et al. 1974; Rueness 1978) and a heteromorphic sexual life history in which a Petrocelis cruenta tetrasporangial stage alternates with a foliose M. stellatus stage (West et al., 1977).

Gametophytic blades are erect, in tufts 5-15 cm tall, firm to leathery, dark red to purple-red, and attached by a spreading crustose base. Axes are compressed to flat, irregularly to dichotomously branched, wide angled, and often with under-rolled thickened edges (channeled). Spermatangia are rare, surficial on papillae, while cystocarps are immersed on papillae. Carpospores may be the result of sexual reproduction or by apomictic divisions (Bird and McLachlan 1992).

Tetrasporophytes form purple-black patches 50 cm wide, 2 mm thick and are closely adherent. They are red-brown in color, often have concentric zones, and are mucilaginous but firm. Older crusts are greenish and are thick and gelatinous. Tetrasporangia are cruciate, intercalary, and in the vertical filaments.


Similar genera:

Chondrus crispus, but it lacks proliferous cystocarps, is lighter in color and does not have encurled edges


Human health:

Intake of Mastocarpus stellatus could promote an improved lipid profile in the serum and a better antioxidant status in the caecum of healthy rats. M. stellatus intake might also be useful for the prevention of hyperlipidemia and thrombosis (Gomez-Ordonez et al. 2012).


Carrageenan from red algae such as M. stellatus has been used as polymer matrix in oral extended-release tablets, aid for the production of pellets, a carrier/stabilizer in micro/nanoparticle systems, and as a gelling/viscosity enhancer in controlled drug release and prolonged retention. Also, there has been for tissue regeneration with therapeutic bio-macromolecules (Li et al. 2013).

Industrial value

Production of biodegradable films and coatings for food have seemed successful from the biopolymers extracted from Mastocarpus stellatus. The K/I-hybrid carrageenan along with starch extracted from cork oak have lengthened the shelf life and increased the visual pleasantness of some fruits (Larotonda, 2012).


The perennial gametophytic blades are very common in the North Atlantic; they grow on vertical and horizontal rocks in the lower littoral and shallow sublittoral zones often forming dense carpets just above Chondrus crispus . They occur on open coastal areas and in estuarine tidal streams. Tetrasporophytic crusts are common, but often overlooked , growing within the mid littoral to shallow sublittoral zones.




Bird. C., and J. McLachlan 1976. Investigations of the marine algae of Nova Scotia. XII. The flora of Pomquet Harbor. Can. J. Bot. 54: 2726-2737

Chen, L. C., T. Edelstein and J. McLachlan 1974. The life history of Gigartina stellata (Stackh.) Batt. (Rhodophyceae, Gigartinales) in culture. Phycologia 13: 287-294.

Edelstein, T., L. C.-M Chen, and J. McLachlan. 1974. The reproductive structures of Gigartina stellata (Stackh.) Batt. (Gigartinales, Rhodophyceae) in nature and culture. Phycologia 13: 99-107.

Gomez-Ordonez, E., A. Jimenez-Escrig, P. Ruperez 2012. Effects of the red seaweed Mastocarpus stellatus intake on lipid metabolism and antioxidant status in healthy Wistar rats. Food Chemistry 135:806-811

Guiry, M.D. and G.M. Guiry 2014. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 08 May 2014.

Larotonda, F.D.S. 2012. Biodegradable films and coatings obtained from carrageenan from Mastocarpus stellatus and starch from Quercus suber. Departamento de Engenharia Quimica. 1: 275-281

Li, L., R. Ni, Y. Shao, S. Mao 2013. Carrageenan and its applications in drug delivery. Carbohydrate Polymers. 103: 1-11.

Mathieson, A. C., and R. L. Burns 1975. Ecological studies of economic red algae. V. Growth and reproduction of natural and harvested populations of Chondrus crispus Stackhouse in New Hamsphire. J. Exp. Mar. Biol. Ecol. 17: 137-156.

Rueness, J. 1978. A note on development and reproduction in Gigartina stellata (Rhodophycae, Gigartinales) from Norway. Br. Phycol. J. 13: 87-90.

Taylor, W. R. 1957. Marine Algae of the Northeastern Coast of North America. Revised edition. Univ. Michigan Press., Ann Arbor, ix + 509 pp. (as Gigartina stellata)

West, J. A., A. R. Polanshek, and M. D. Guiry 1977. The life history in culture of Petrocelis cruenta J. Agardh (Rhodophyta) from Ireland. Br. Phycol. J. 12: 45-53.