Phytoplankton

Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria of the phylum Cyanobacteriota that can obtain biological energy via oxygenic photosynthesis. Cyanobacteria apparently originated in a freshwater or terrestrial environment, and first appeared in the middle Archean eon. They are probably the most numerous taxon to have ever existed on Earth. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteria's informal common name, blue-green algae.

A diatom (Neo-Latin diatoma) is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's biomass. They generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion tonnes of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms are a significant component of marine sediment, and the entire Amazon basin is fertili

Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from Ancient Greek φυτόν (phutón), meaning "plant", and πλαγκτός (planktós), meaning "drifter, wanderer, roamer", and thus, "plant drifter".

class of algae

The haptophytes, classified either as the Haptophytina, Haptophyta or Prymnesiophyta (named for Prymnesium), are a clade of algae that can produce minerals.

thumb|upright=1.1|Coccolithophore cells are covered with protective calcified (chalk) scales called coccoliths