demersal
adjective
de·mer·sal di-ˈmər-səl 
: living near, deposited on, or sinking to the bottom of the sea
demersal fish eggs
Example Sentences
Recent Examples on the Web The muscles of European sea bass contain little plastic, but the stomachs of British demersal sharks contain significant quantities. 
Rafil Kroll-zaidi, Harper's Magazine, 15 Sep. 2020
Rafil Kroll-zaidi, Harper's Magazine, 15 Sep. 2020 Word History
Etymology
Latin demersus (past participle of demergere to sink, from de- + mergere to dip, sink) + English -al entry 1 — more at merge
First Known Use
1889, in the meaning defined above