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
Caudal luring difference is in the snake's posture and especially in the nature and outcome of the behaviour in reference to the encounter with prey. Other caudal luring-like movements occur as warning signals and are induced by stressful circumstances. Thus identifying caudal luring entails observing the effect that tail movements have on prey species, a burden of evidence that is woefully lacking in much of the literature on this intriguing behaviour. Caudal luring Caudal luring is the use of tail movements by a predator to attract prey animals that think the tail is a worm or other smaller prey and approach within