You searched for: “bathyplanktonic
bathyplanktonic (adjective) (not comparable)
Regarding lifeforms that only drift up towards the surface of the sea at dusk, otherwise they are below the bathyal zone: James read about bathyplanktonic organisms for his biology class at school and found out that they underwent a vertical movement towards the depth of a sea during the day, and only rising during the night.
This entry is located in the following unit: plankto-, plankt-, -plankton (page 1)