benthic

benttinen Pertaining to the benthos; living on the seafloor, as opposed to floating in the ocean.
1878, Proceedings of the United States National Museum, Smithsonian Institution Press, p. 3:

The benthic environment, except for intertidal areas, has been scarcely explored...

As the classical approach to benthic community studies originated primarily with Danish biologists, a section is devoted to comparisons of Danish bottom communities with those obtained in Hadley Harbor.

Benthic foraminifera have been used for stratigraphic purposes almost since they began to be studied systematically.