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Plankton composed of organisms, including both phytoplankton and zooplankton, measuring from 20 to 200 micrometers.


(Biology) a very small plankton, esp a microscopic plankton


(ˌmaɪ kroʊˈplæŋk tən)

plankton visible as individual organisms only with the aid of a microscope.
References in periodicals archive ?
Effects of pulp and paper mill effuents on the microplankton and microbial self-purification capabilities of the Biobio River, Chile, Sci.
The spindle-shaped microfossils are from 20 to 60 microns in length, about the size of fine sand and within the size range of today's microplankton.
After studying microplankton remains in sediment from below, between and above the second-phase lava flows, the researchers observed that the number of living species dropped 50 percent at the onset of eruptions.
Counting and measuring living Protozooplankton using a video enhanced microscope and a new microplankton concentration device.
A probe measured the currents under the shelf, which were strong enough to deliver tiny creatures called microplankton to the area.
However, the team reports in the January Paleoceanography that instruments on the probe measured currents strong enough to bring in microplankton that form the base of the site's food chain.