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Microcystis

noun
Mi·​cro·​cys·​tis

Definition of Microcystis

: a genus of unicellular blue-green algae (family Chroococcaceae) forming irregularly shaped colonies within a common gelatinous envelope and including at least one species (M. aeruginosa) that is poisonous and may become abundant and troublesome in lakes especially where much organic matter is present

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History and Etymology for Microcystis

New Latin, from micr- + -cystis

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