Adult Copepod
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Identifying Characteristics:
  • Copepods are typically 0.04 to 0.08 inches long, with a teardrop shaped body and large antennae.
  • Although like other crustaceans they have an armored exoskeleton, they are so small that in most species this thin armor, and the entire body, is almost totally transparent.
  • Most copepods have a compound, median single eye, usually bright red and in the center of the transparent head
  • Like other crustaceans, copepods possess two pairs of antannae; the first pair are often long and conspicuous.
  • Copepods typically have a short, cylindrical body, with a rounded or beaked head.
  • The head is fused with the first one or two segments, while the remainder of the thorax has from three to five segments, each with limbs.

Special Adaptations:
  • Copepods are sometimes used as bioindicators. These biological indicators are species used to monitor the health of an environment or ecosystem.
  • Because of their small size, copepods have no need of any heart or circulatory system. This means they need less energy in order to function completely.
  • Many benthic copepods eat organic detritus or the bacteria that grow in it, and their mouth parts are adapted for scraping. This means they can scavenge the water for food more easily.

The Reef Tank. Fun Facts about Live Amphipods and Copepods. Retrieved August 22, 2012, from
Wikipedia: The Free Encyclopedia. Copepod. Retrieved August 22, 2012, from

Katherine Johnson