#diatom  microscopic unicellular marine or freshwater colonial alga having cell walls impregnated with silica
  supertype:  alga__algae  primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves
  member of:  class_Bacillariophyceae__Bacillariophyceae__Diatomophyceae__class_Diatomophyceae  marine and freshwater eukaryotic algae: diatoms
     member of:  division_Chrysophyta__Chrysophyta  mostly freshwater eukaryotic algae having the chlorophyll masked by brown or yellow pigment; yellow-green and golden-brown algae and diatoms: Xanthophyceae, Chrysophyceae, Bacillariophyceae; some some classification systems superseded or subsumed by Heterokontophyta
        member of:  kingdom_Protoctista__Protoctista  in most modern classifications, replacement for the Protista; includes: Protozoa; Euglenophyta; Chlorophyta; Cryptophyta; Heterokontophyta; Rhodophyta; unicellular protists and their descendant multicellular organisms: regarded as distinct from plants and animals

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