Opah

Lampris guttatus is a large discoid and deeply keeled fish with a conspicuous coloration. They can reach a maximum length of 2 m (6.6 ft) and a maximum weight of 86 kg (190 lb), although there are reports of the fish reaching up to 270 kg (600 lb). The body is a deep steely blue grading to rosy on the belly, with white spots in irregular rows covering the flanks. Both the median and paired fins are a bright vermillion. Jaws are vermillion, too. The large eyes stand out as well, ringed with golden yellow. The body is covered in minute cycloid scales and its silvery, iridescent guanine coating is easily abraded.

Lampris guttatus has a worldwide distribution, from the Grand Banks to Argentina in the Western Atlantic, from Norway and Greenland to Senegal and south to Angola in the Eastern Atlantic (also in the Mediterranean), from the Gulf of Alaska to southern California in the Eastern Pacific, in temperate waters of the Indian Ocean, and rare forays into the Southern Ocean.

The life history and development of L. guttatus remains rather uncertain. They are apparently solitary, but are known to school with tuna and other scombrids. They propel themselves by a lift-based mode of swimming using their pectoral fins. This, together with their forked caudal fins and depressible median fins, indicates that they swim at constantly low speeds. They are able to swim at over 25 cm/s, and one was even observed reaching 4 m/s (14 km/h; 8.9 mph) in a burst of speed.

Like many other large pelagic visual predators, such as swordfish and big-eye tuna, they exhibit vertical behavior. Based on those caught off the Hawaiian coast, squid and krill make up the bulk of their diet, though they also consume small fish. Those caught along the Patagonian Shelf also showed a narrow range of prey, the most common of which was the deepwater onychotenhid squid (Moroteuthis ingens).

L. guttatus is often regarded as a secondary target in commercial fisheries, and is taken incidentally while longline fishing for other pelagic species like tuna. It has been described to have a rich and creamy flavor, and are commonly used in sashimi.