kieuwdeksel
Kieuwdeksel, or operculum, is a curved bony plate on each side of a fish’s head that covers and protects the gills. In most bony fishes the operculum forms part of a gill-cover apparatus built from several bones, including the main opercular plate (opercle) and adjacent elements such as the subopercular and preopercular bones.
The operculum serves two primary roles: protection of delicate gill tissue and participation in respiration. Most
Variation and distribution: The operculum is a characteristic feature of most bony fishes (osteichthyes). Cartilaginous fishes
Evolution and significance: The operculum is an important adaptation that allows independent regulation of water flow