Neuston

Neuston is the collective term for the organisms that float on the top of water (epineuston) or live right under the surface (hyponeuston). Neustons are made up of some species of fish (see flying fish), beetles (see whirligig beetle), protozoans, bacteria and spiders (see fishing spider and diving bell spider). Collembola in the genera Podura and Sminthurides are almost exclusively neustonic, while Hypogastrura species often aggregate on pond surfaces. A water strider, Gerris, is a common example of an insect that supports its weight on water's surface tension.

Other uses of the word

By extension, the term may also refer to non-organismal floating aggregations (see, e.g., Great Pacific Garbage Patch).

Contrasts with other aquatic life

Contrast the terms plankton (the organisms that float or drift within the water), nekton (the organisms that swim, powerfully, in the water), and benthos (the organisms on the bottom of a body of water).

Neuston sometimes refers to only that subset of floating organisms that are microscopic or those that rely on surface tension to float. The term pleuston refers to superset including those organisms that float by buoyancy or are macroscopic.