Individual #Pennsylvanian_period__Pennsylvanian__Upper_Carboniferous__Upper_Carboniferous_period  from 280 million to 310 million years ago; warm climate; swampy land
  part of:  Carboniferous_period
  type:  geological_period__period  a unit of geological time during which a system of rocks formed; "ganoid fishes swarmed during the earlier geological periods"

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