Home / Rhodophyceae / Macroreds / Laurencia
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Name derivation:
Laurencia= probably named for Jean Baptiste Auguste Francois Marie la Laurencie, a French naturalist in the late 1800s
Classification:
Order Ceramiales; Family Rhodomelaceae. There are at least nine common species.
Morphology:
Algae are erect, usually bushy, fleshy to cartilaginous, and with one or more main axes arising from a common discoid holdfast. Axes are polysiphonous, the four pericentral cells are usually covered by dense cortication. The medulla contains large hyaline cells; cortex has small cells with pigmented surface cells that may have secondary pit connections and a corps en cerise. Branching is radial or pinnate and branches arise from basal cells of apical trichoblasts. Branchlets are usually short and club-shaped or basally constricted and expanded to blunt tips that have a pit with an apical cell and tufts of branched trichoblasts. Tetrasporangia tetrahedrally divided.
Similar genera:
Laurencia is closely related phylogenitcally to Chondria. The genus Laurencia was recently split into three genera: Laurencia, Chohdrophycus and Osmundea (Garbary and Harper 1998, Nam 1999). Laurencia, Chondrophycus, Osmundea and Palisada are difficult to separate using vegetative features.
Habitat:
Marine sublittoral benthos. Primarily tropical or subtropical, often in the vicinity of islands.
Secondary metabolites:
Laurencia spp. are the major source of secondary metabolites currently listed in the Marine Seaweed Metabolite Database (Davis and Vasanthi 2011). Some of these have important bioactivity such as cytotoxicity or antimalarial properties. Many include a halogen atom in their molecular structure, and are in the mass range of 200 – 700 atomic mass units.
References:
Abbott, I. A,. and G. J. Hollenberg. 1976, Marine Algae of California. Stanford University Press, Stanford, xii + 827 pp Davis, G.D.J. and A.H.R. Vasanthi 2011. Seaweed metabolite database (SWMD): A database of natural compounds from marine algae. Bioinformation 5(8):361-364. online Garbary,D.J. and J.T. Harper 1998. A phylogenetic analysis of the Laurencia complex (Rhodomelaceae, Rhodophyta) in southern Australia. Aust. J. Blt. 35:477-565. Nam, K.W. (1999). Morphology of Chondrophycus undulata and C. parvipapillata and its implications for the taxonomy of the Laurencia (Ceramiales, Rhodophyta) complex. Eur. J. Phycol. 34: 455-468.