Operculum (fish) required, such as ventilation.. Operculum (fish) The operculum is a series of bones found in bony fish that serves as a facial support structure and a protective covering for the gills; it is also used for respiration and feeding. The opercular series contains four bone segments known as the preoperculum, suboperculum, interoperculum and operculum. The preoperculum is a crescent-shaped structure that has a series of ridges directed posterodorsally to the organisms canal pores. The preoperculum can be located through an exposed condyle that is present immediately under its ventral margin; it also borders the operculum, suboperculum, and interoperculum posteriorly. The
Pomadasys stridens Pomadasys stridens Pomadasys stridens, the striped piggy or lined piggy, is a grunt from the western Indian Ocean, it is one of a group of Indo-Pacific marine species which have colonised the Mediterranean Sea through the Suez Canal from the Red Sea, a process known as Lessepsian migration. "Pomadasys stridens" has a silvery body which is slightly darker dorsally than it is ventrally, it has 3-4 golden-brown stripes along its body, merging towards the caudal peduncle, and a dark blotch on the operculum. It has a relatively large head with a small, slightly oblique mouth and two pores on the