microplankton

(from the article `plankton`) ...can be collected with a coarse net, and morphological details of individual organisms are easily discernible. These forms, one millimetre or more ... During the time interval between 200 and 65 million years ago, but especially from 100 to 65 million years ago, microplankton abundance and diversity ... ...
Found on http://www.britannica.com/eb/a-z/m/86

microplankton

microplankton Small (tiny) planktonic organisms.
Found on http://www.wordinfo.info/words/index/info/view_unit/1308/4
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