nounpl. -·nas or -·nae
the animals living on the surface of marine or freshwater sediments
Origin of epifaunaepi- + fauna
Aquatic animals, such as starfish, flounder, or barnacles, that live on the surface of a sea or lake bottom or on the surface of a submerged substrate, such as rocks or aquatic plants and animals, but that do not burrow into or beneath the surface.