water flea

American  

noun

1. any of various small crustaceans that move about in the water like fleas, as those of the genus Daphnia.

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water flea British  

noun

1. any of numerous minute freshwater branchiopod crustaceans of the order Cladocera, which swim by means of hairy branched antennae See also daphnia

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Etymology

Origin of water flea

First recorded in 1575–85

Example Sentences

But evidence of the potential effects of PVA “are scarce,” said Magni, who co-authored a study that did not find toxic effects associated with the compound in fish embryos and a species of water flea.

From Washington Post • Nov. 15, 2022

The water flea Daphnia magna—a freshwater crustacean up to a few millimeters in size—is one species busy evolving in cities in response to heat, pollution and even local predators.

From Scientific American • Mar. 25, 2022

Daphne, named after daphnia, a type of water flea, credited with helping clear the waters of Lake Washington of blue-green algae after sewage stopped regularly flowing into the lake in the 1960s.

From Seattle Times • Mar. 27, 2021

That testing involves students helping to constantly breed fathead minnows and Ceriodaphnia dubia, a species of water flea that is used in testing water quality.

From Washington Times • Sep. 11, 2017

A little water flea was described as a separate genus, Nauplius, before it was known to be the larva of a higher water flea, and so also Leptus was thought to be a mature mite.

From Our Common Insects A Popular Account of the Insects of Our Fields, Forests, Gardens and Houses by Packard, A. S. (Alpheus Spring)