Coccolithophore (Emiliania huxleyi)
Coccolithophores are single-celled algae, or phytoplankton, belonging to the haptophytes. They are distinguished by special calcium carbonate plates (or scales) of unknown purpose called coccoliths, which are important microfossils. Coccolithophores are exclusively marine and are found in large numbers throughout the surface euphotic zone of the ocean. An example of a globally significant coccolithophore is Emiliania huxleyi.
Due to their microscopic size and broad distribution of many taxa, coccoliths (calcareous nannoplankton) have become very popular for solving various stratigraphic problems, and many studies have been devoted to that end. Nanofossils are sensitive indicators of changes in the temperature and salinity of the ocean and sea surface water. Quantitative analysis of calcareous nanoplankton assemblages is being employed to reveal such changes.
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