Pyrocystis fusiformis is a non-motile, tropical, epipelagic, marine dinoflagellate (flagellate microorganisms), reaching lengths of up to 1 millimetre (0.039 in).

[2] P. fusiformis is non-motile, which is a characteristic of all members of family Pyrocystaceae, which lose their flagellum by the time these organisms are adults.

[6] P. fusiformis will only photosynthesize during daylight hours and mostly produce bioluminescence during night because of their circadian rhythm which controls both processes.

[10] In P. fusiformis bright blue light is produced through the reaction of the enzyme luciferase and protein-like compound luciferin in the cell's plasma membrane.

[2] Some oxygen produced by phytoplankton is dissolved into marine waters and helps support respiration for heterotrophic organisms.

[14] Phytoplankton also form the basis of the marine food chain and are preyed upon by various organisms, such as grass shrimp, mosquito fish, mysids,[6] and copepods.

[3] P. fusiformis is also able to take advantage of surplus carbon (C) in surface waters by using what it needs for metabolic processes immediately, and then catabolizing and storing excess C for use at greater depths, allowing it have a relatively constant rate of cell division throughout the euphotic zone.

[18] P. fusiformis is interesting to humans as a natural phenomenon to observe in the ocean, in addition to being easily cultivated in a controlled environment at home and in classrooms for study.

Working with scientists at the Scripps Institution of Oceanography, Blumenfeld photographs P. fusiformis in order to "activate a dialogue about our natural environment and our relationship to it.