- copepod
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/koh"peuh pod'/, n.any of numerous tiny marine or freshwater crustaceans of the order (or subclass) Copepoda, lacking compound eyes or a carapace and usually having six pairs of limbs on the thorax, some abundant in plankton and others parasitic on fish.[1830-40; < NL Copepoda name of the order < Gk kópe a handle, oar + -poda -PODA]
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Any of the 10,000 known species of crustaceans in the subclass Copepoda.Copepods are widely distributed and ecologically important, serving as food for many species of fish. Most species are free-living marine forms, found from the sea's surface to great depths. Some live in freshwater or in damp vegetation; others are parasites. Most species are 0.02–0.08 in. (0.5–2 mm) long. The largest species, a parasite of the fin whale, grows to a length of about 13 in. (32 cm). Unlike most crustaceans, copepods have no carapace. Nonparasitic forms feed on microscopic plants or animals or even on animals as large as themselves. Members of the genus Cyclops (order Cyclopoida) are called water fleas. See also guinea worm.Copepods (Temora)Douglas P. Wilson* * *
any member of the widely distributed crustacean subclass Copepoda. Copepods are of great ecological importance, providing food for many species of fish. Most of the 10,000 known species are free-living marine forms, occurring throughout the world's oceans. Copepods are key components of marine food chains and serve either directly or indirectly as food sources for most commercially important fish species. Some live in freshwater; a few live in damp moss, in moisture at the base of leaves, or in humus. Some species are parasitic (parasitism). Water fleas (genus Cyclops), microscopic freshwater species of the order Cyclopoida, can transmit the guinea worm to humans.Most copepods are 0.5 to 2 mm (0.02 to 0.08 inch) long. The largest species, Pennella balaenopterae, which is parasitic on the finback whale, grows to a length of 32 cm (about 13 inches). Males of Sphaeronellopsis monothrix, a parasite of marine ostracods, are among the smallest copepods, attaining lengths of only 0.11 mm.Copepods lack compound (i.e., multifaceted) eyes. Unlike most crustaceans, they also lack a carapace—a shieldlike plate over the dorsal, or back, surface. Some species feed on microscopic plants or animals; others prey on animals as large as themselves. Parasitic forms suck the tissues of the host. Most species reproduce sexually, but certain forms also reproduce by parthenogenesis—i.e., the eggs develop into new individuals without being fertilized by the male.* * *
Universalium. 2010.