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

Based on laboratory tests, scientists who documented soaring acidity in the German reservoirs found it can imperil a type of water flea by hampering defense from predators.

From Seattle Times

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

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

“Typically this type of paddling is seen in small aquatic crustaceans such as water fleas,” says Santhanakrishnan, who was not involved with the study.

From Scientific American

The migration was first documented in the early 1800s, when naturalist Georges Cuvier noted that plankton called daphnia—water fleas—were disappearing and reappearing in a daily cycle in a shallow freshwater lake.

From Scientific American