Halibut Halibut Halibut is a common name principally applied to the two flatfish in the genus "Hippoglossus" from the family of right-eye flounders. Less commonly, and in some regions only, other species of flatfish are also referred to as being halibuts. The word is derived from "haly" (holy) and "butte" (flat fish), for its popularity on Catholic holy days. Halibut are demersal fish and are highly regarded as a food fish. The Pacific halibut is the world's largest flatfish. The IGFA record was apparently broken off the waters of Norway in July 2013 by a 515-pound 8.6 foot fish. This was
Demersal fish benthic fish are denser, with negative buoyancy so they can lie on the bottom without any effort. Most demersal fish are benthopelagic. As with other bottom feeders, a mechanism to deal with substrate is often necessary. With demersal fish the sand is usually pumped out of the mouth through the gill slit. Most demersal fish exhibit a flat ventral region so as to more easily rest their body on the substrate. The exception may be the flatfish, which are laterally depressed but lie on their sides. Also, many exhibit what is termed an "inferior" mouth, which means that the mouth