Kappaphycus alvarezii

Kappaphycus alvarezii (syn. K. cottonii; Eucheuma cottonii) is a species of red algae. It is one of the most important commercial sources of carrageenans, a family of gel-forming, viscosifying polysaccharides. Farming methods affect the character of the carrageenan that can be extracted from the seaweed.