hyponeuston

CONT: On désigne sous le nom général de neuston le peuplement de l'interface océan-atmosphère. On peut y distinguer un épineuston, représenté par des animaux qui sont sur l'interface [...] et un hyponeuston qui habite les premiers centimètres d'eau.

CONT: There is also a surface film community (neuston) which, when richly developed, forms a 'water bloom'. This only occurs on small bodies of water where the surface is protected from wind. The algae, together with some bacteria and invertebrates, become attached to the boundary layer between the air and water, either on the upper surface of the water (epineuston) or on the under surface (hyponeuston).
CONT: [the hyponeuston] are associated with the underside of the film and project into the water below.