An agarophyte is a

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), '' Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

, usually a

red alga Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species within over 900 Genus, genera amidst ongoing taxon ...

, that produces the

hydrocolloid A colloid is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance. Some definitions specify that the particles must be dispersed in a liquid, while others exten ...

agar Agar ( or ), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from " ogonori" and " tengusa". As found in nature, agar is a mixture of two components, t ...

in its

cell wall A cell wall is a structural layer that surrounds some Cell type, cell types, found immediately outside the cell membrane. It can be tough, flexible, and sometimes rigid. Primarily, it provides the cell with structural support, shape, protection, ...

s. This agar can be harvested commercially for use in biological experiments and culturing. In some countries (especially in the developing world), the harvesting of agarophytes, either as natural stocks or a cultivated crop, is of considerable economic importance. Notable genera of commercially exploited agarophytes include ''

Gracilaria ''Gracilaria'', also known as irish moss or ogonori, is a genus of red algae in the family Gracilariaceae. It is notable for its economic importance as an agarophyte meaning that it is used to make agar, as well as its use as a food for humans ...

'' and ''

Gelidium ''Gelidium'' is a genus of thalloid red algae comprising 134 species. Its members are known by a number of common names.Recorded common names are tengusa, makusa, genso, niu mau tsai, japansche scheleiachtige mos, steen-or klipbloem, hay tsay, ol ...

'' (such as ''

Gelidium amansii ''Gelidium amansii'', also known as by its Korean name ''umutgasari'', is an economically important species of red algae commonly found and harvested in the shallow coast (3 to 10 m or 10 to 33 ft of depth below the water) of many East Asia ...

'' and ''

Gelidium corneum ''Gelidium'' is a genus of thalloid red algae comprising 134 species. Its members are known by a number of common names.Recorded common names are tengusa, makusa, genso, niu mau tsai, japansche scheleiachtige mos, steen-or klipbloem, hay tsay, o ...

'').

References

Seaweeds {{Rhodophyta-stub