pleuston

biological organism

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Last updated

July 1, 2026

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Pleuston refers to organisms that live in the thin surface layer at the air-water interface of a body of water. These organisms are distinct from plankton, which drift passively, and nekton, which are active swimmers. While plankton are found within the water column, pleuston exist on the surface. Examples of pleuston include large floating seaweeds like Sargassum. The term "pleustonic" is an adjective used to describe something related to or having the characteristics of pleuston.123

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marine ecosystem
Physical and chemical properties of seawater
…surface of the water (pleuston) and sails with the assistance of a modified flotation chamber—contrasts sharply with the sleek, elongated shape of the barracuda.
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…surface of the water (pleuston) and sails with the assistance of a modified flotation chamber—contrasts sharply with the sleek, elongated shape of the barracuda.
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plankton
…are not considered plankton but pleuston. Pleuston are forms of life that live at the interface of air and water. Organisms resting or swimming on the surface film of the water are called neuston (e.g., the alga Ochromonas).
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…are not considered plankton but pleuston. Pleuston are forms of life that live at the interface of air and water. Organisms resting or swimming on the surface film of the water are called neuston (e.g., the alga Ochromonas).
Read More