- cyanobacteria, blue-green algae - predominantly photosynthetic prokaryotic organisms containing a blue pigment in addition to chlorophyll; occur singly or in colonies in diverse habitats; important as phytoplankton
--1 is a kind of eubacteria, eubacterium, true bacteria
--1 is a member of class Cyanobacteria, Cyanophyceae, class Cyanophyceae
--1 has particulars: nostoc; trichodesmium