benthos

organisms living on or in the bottom of oceans, seas, rivers, lakes and other water bodies. [JVG] Depending on the size of the organisms, benthos is regarded as macrobenthos (organisms > 1000 µm), meiobenthos (organisms between 42 µm and 1000 µm) and nanobenthos or microbenthos (organisms < 42 µm). Depending on the depth distribution, benthos is regarded as epibenthos (living between low water line and 200 m depth), mesobenthos (living at depths between 200 and 1000 m), hypobenthos (living between 1000 and 2000 m) and abyssal benthos (living below 2000 m).