What does a copepod look like?

Copepods are small crustaceans that are found in all aquatic environments, with greatest diversity in the ocean's pelagic zone and in fresh water. They are planktonic, meaning that they drift with the currents and do not have the ability to swim against the current. Copepods are typically less than 1 mm long, with slender, transparent bodies and two pairs of antennae. The front pair of antennae is used for sensing and the second pair is used for swimming. Copepods also have a pair of mandibles, two pairs of maxillae, and a single pair of maxillipeds. The mandibles are used for biting, the maxillae are used for manipulating food, and the maxillipeds are used for grasping food. The body is elongated, with a distinct segmentation, and the head has two large compound eyes. The first pair of antennae is long and uniramous, while the second pair is shorter and biramous. The mandibles are strong and toothed, and the maxillipeds are prehensile. The female carries the eggs in one or more sacs attached to the body.

Copepods are the most numerous multicellular animals on the planet, with an estimated population size of 1028. They play an important role in the marine food chain as they are a major source of food for fish and baleen whales.