benthos

n. plants and animals living on the ocean floor

Benthos are the organisms which live on, in, or near the seabed, also known as the benthic zone. Although the term derived from the Greek for "depths of the sea", the term is also used in freshwater biology to refer to organisms at the bottoms of freshwater bodies of water, such as lakes, rivers, and streams.
See more at Wikipedia.org...

Benthos bottom of the sea or other body of water; said of cyanobacteria which grow on submerged rocks in alpine lakes and cause sudden death in [more]Benthos - Community and Resources

Noun
1. a region including the bottom of the sea and the littoral zones
(synonym) benthic division, benthonic zone
(hypernym) biogeographical region
2. organisms (plants and animals) that live at or near the bottom of a sea
(hypernym) organism, being

n. benthos, plants and animals living on the ocean floor