Diatom: Quick Facts

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Facts

Also Known As	Bacillariophyceae

Photos and Videos

Microscope view of assorted diatoms with varied geometric shapes and translucent blue and gold coloring, living among sea ice crystals in McMurdo Sound, Antarctica.

Highly magnified view of a single diatom, showing a circular, symmetrical structure with intricate radial patterns and a textured, translucent surface.

diatoms; radiolarians

Algae exist in many different shapes and sizes and have complex evolutionary relationships with other organisms, including fungi and protists. One example of a group of algae that exist in different shapes are the diatoms (class Bacillariophyceae), which may be round (centric) or elongated (pennate). Species of diatoms in the genus Stauroneis are pennate.

Figure 2: Unicellular and colonial algae. (From top) Drapomaldia, Stauroneis, Hyalotheca, Diatom, Phaeoplaca, Bambosina.

Diagram showing the cycling of silica in the marine environment, with arrows illustrating processes such as river influx, inorganic adsorption, biological fixation by radiolarian and diatom skeletons, dissolution, deposition as opaline skeletal debris, upwelling, and hydrothermal activity, all within labeled ocean zones.

Illustration of an ocean food chain showing sunlight supporting one-celled life like dinoflagellates and diatoms, which are eaten by shrimplike copepods. These are consumed by small fish, which are then eaten by mackerel, followed by tuna, and finally a large shark at the top of the food web.

How phytoplankton function and survive in the ocean

Observe diatoms, microscopic sea organisms encased in silicified cell walls with intricate designs

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Topics

Centrales Bacillaria Pennales Navicula Cyclotella Thalassiosira Nitzschia diatomaceous earth diatom ooze diatomite Brown algae Yellow-green algae Golden algae Chloromonad

Key People

Ruth Patrick

Ruth Patrick

American biologist and educator

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Per Teodor Cleve

Swedish chemist