a genus of tiny, freshwater crustaceans having a transparent body, used in biological research and as food for tropical fish.

Compare water flea.

Origin of Daphnia

1840–50; < New Latin, perhaps after Daphne; see -ia
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Examples from the Web for daphnia

Historical Examples of daphnia

  • Wolfgang Ostwald has produced experimentally, through variation of temperature, dimorphism of form in Daphnia.

  • Such small creatures as Daphnia pulex, Cyclops quadricornis and Rotifera should be introduced into ponds.

    Amateur Fish Culture

    Charles Edward Walker

  • Both Daphnia and Cyclops are bred in stagnant water in which there should be a good stock of weeds.

    Amateur Fish Culture

    Charles Edward Walker

  • Daphnia must be reared in a stagnant pond, the fresh-water shrimp (Gammarus pulex) in running water, with plenty of weeds.

    Amateur Fish Culture

    Charles Edward Walker

  • Some of these belong to the genus Daphnia, and differ from the species found in other situations by their glassy transparency.

    The Life of Crustacea

    William Thomas Calman

British Dictionary definitions for daphnia



any water flea of the genus Daphnia, having a rounded body enclosed in a transparent shell and bearing branched swimming antennae

Word Origin for daphnia

C19: from New Latin, probably from Daphne
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012