Spinossum / Eucheuma DenticulatumUpdate: 3/16/2015
Eucheuma denticulatum, a perennial red seaweed, is composed of rigid clumps of low-growing, cartilaginous thalli. These clumps can range in size depending on growing conditions, but are able to reach considerable size, up to 50 centimeters in length and weighing over 1 kilogram. The primary axis and regularly spaced branches are cylindrical, each bearing whorled spinose (spine-like) branchlets which sometimes develop into secondary lateral branches. This one species can be found in a variety of shades from brown to green to red, especially when cultivated. Eucheuma denticulatum is most commonly found growing on coarse sand to rocky substrates in the intertidal to shallow subtidal zone where it is exposed to strong currents and wave action. This algae has the unique ability of its branches to form secondary holdfasts to other plants as well as the substrate, forming thick carpet-like beds of seaweed where individual plants are hard to distinguish. This growth pattern coupled with the strength of the holdfasts enables Eucheuma denticulatum to withstand such strong water movement without being torn up or shredded. Quite the contrary, it seems to prefer such a harsh environment as it has never been recorded in calm or protected habitats. Cultivated Eucheuma denticulatum grows most rapidly in areas of strong tidal currents, higher salinity (away from estuaries), bright light, over bottoms of sand and coral and rock. It is a similar species to Kappaphycus alvarezii.