|Compare plankton the population of free-swimming animals that inhabits the middle depths of a sea or lake|
|[C19: via German from Greek nēkton a swimming thing, from nēkhein to swim]|
the assemblage of pelagic animals that swim freely, independent of water motion or wind. Only three phyla are represented by adult forms. Chordate nekton include numerous species of bony fishes, the cartilaginous fishes such as the sharks, several species of reptiles (turtles, snakes, and saltwater crocodiles), and mammals such as the whales, porpoises, and seals. Molluscan nekton include the squids and octopods. The only arthropod nekton are decapods, including shrimps, crabs, and lobsters.
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