There are two living members of this genus, one is found in tropical and temperate waters in most oceans, while the other is restricted to the Southern Ocean. These deep-water fish are prized by anglers, as they are rarely caught, though are sometimes caught as a bycatch from commercial tuna fishing. Opah flesh is sometimes used in fish markets, for example, in Sushi.
These deeply-keeled, discoid fish are deep red-orange to rosy belly, with white spots covering the flanks. It has large eyes, and it's silvery and guanine coating is easily abraded.
The larger of the two species, L. guttatus, can reach 2m and weigh 270kg, while the smaller and lesser known L. immaculatus can reach 1.1m.
Very little is known of ecology and biology of Opahs.