Lyngbya is a genus of cyanobacteria, unicellular autotrophs that form the basis of the oceanic food chain.

As a result of recent genetic analyses, several new genera were erected from this genus: e.g., Moorea,[2] Limnoraphis,[3] Okeania,[4] Microseira,[5] and Dapis.

[6] Lyngbya species form long, unbranching filaments inside a rigid mucilaginous sheath.

[8] Some Lyngbya species cause the human skin irritation called seaweed dermatitis.

[9] Some Lyngbya species can also temporarily monopolize aquatic ecosystems when they form dense, floating mats in the water.