Taxonomy and life forms in the plankton

At the opposite end of the taxonomic hierarchy from domain, kingdom and phylum, is the fundamental category of species, defined (Kelly McGrath, 1975) as  

Group Typical marine planktonic forms Example genera 

Prokaryote domain (EU) BACTERIA PROTEOBACTERIA Gram-negative bacteria, primitively photosynthetic or chemolithotrophic, with several groups that developed aerobic respiration original source of mitochondria of eukaryotes includes anaerobic PA, chemo-autotrophs (e.g. ammonium oxidisers), oxygen or nitrate respiring H pseudomonads Nitromonas, Pseudomonas 

CYANOBACTERIA/ Cyanophyta/ Cyanophyceae Cyanobacteria PA blue-green algae , mostly contain phycobiliprotein filiamentous or otherwise colonial Oscillatoriales and heterocystous Nostocales include N-fixers picoplanktonic members in Chroococcales and Chloroxybacteria (without phycobiliprotein) Trichodesmium, Synechococcus, Prochlorococcus 

ALVEOLATA Ciliophora Ciliates bearing cilia (same structure as flagella) oligotrichs (H) with few, elaborate groups of cilia functionally PA Mesodinium with symbiotic cryptomonads Strombidium, Tintinnopsis Mesodinium = Myrionecta 

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