#phytoplankton  photosynthetic or plant constituent of plankton; mainly unicellular algae
  supertype:  #plant__flora__plant_life__plantlife  a living organism lacking the power of locomotion
  subtype:  #planktonic_algae  unicellular algae
  member of:  #plankton  the aggregate of small plant and animal organisms that float or drift in great numbers in fresh or salt water
     member of:  #congeries__congerie__aggregate__conglomeration  a sum total of many heterogenous things taken together

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