Opahs, also commonly known as moonfish, sunfish (not to be confused with Molidae), kingfish, and redfin ocean pan are large, colorful, deep-bodied pelagic lampriform fishes comprising the small family Lampridae (also spelled Lamprididae). The family comprises two genera: Lampris (from the Ancient Greek λαμπρός : lamprós, "brilliant" or "clear") and the monotypic Megalampris (known only from fossil remains). The extinct family, Turkmenidae, from the Paleogene of Central Asia, is closely related, though much smaller. In 2015, Lampris guttatus was discovered to have near-whole-body endothermy in which the entire core of the body is maintained at around 5 °C above the surrounding water. This is unique among fish as most fish are entirely cold blooded or are capable of warming only some parts of their bodies. Species Two living species were traditionally recognized, but a taxonomic review in 2018 found that more should be recognized (the result of splitting L. guttatus into several species, each with a more restricted geographic range), bringing the total to six. The six species of Lampris have mostly non-overlapping geographical ranges, and can be recognized based on body shape and coloration pattern. Lampris australensis Underkoffler, Luers, Hyde & Craig, 2018 Southern spotted opah – Southern hemisphere, in the Pacific and Indian oceans. Lampris guttatus (Brünnich, 1788) North Atlantic opah – formerly thought to be cosmopolitan, but now thought to be restricted to the northeastern Atlantic including the Mediterranean Sea. Lampris immaculatus Gilchrist, 1904 southern opah – confined to the Southern Ocean from 34° S to the Antarctic Polar Front. Lampris incognitus Underkoffler, Luers, Hyde & Craig, 2018 smalleye Pacific opah – central and eastern North Pacific Ocean. Lampris lauta Lowe, 1860 East Atlantic opah – eastern Atlantic Ocean, including the Mediterranean, Azores and Canary Islands. Lampris megalopsis Underkoffler, Luers, Hyde & Craig, 2018 bigeye Pacific opah – cosmopolitan, including the Gulf of Mexico, Indian Ocean, the western Pacific Ocean and Chile. Extinct species † Lampris zatima, also known as "Diatomœca zatima", is a very small, extinct species from the late Miocene of what is now Southern California known primarily from fragments, and the occasional headless specimens. † Megalampris keyesi is an extinct species estimated to be about 4 m in length. Fossil remains date back to the late Oligocene of what is now New Zealand, and it is the first fossil lampridiform found in the Southern Hemisphere. Description Opahs are deeply keeled, compressed, discoid fish with