Word of the Day -- Opah

Lampris guttatus, commonly known as the opah, cravo, moonfish, kingfish, and Jerusalem haddock, is a large, colorful, deep-bodied pelagic lampriform fish belonging to the family Lampridae, which comprises the genus Lampris, with two extant species.

It is a pelagic fish with a worldwide distribution. While it is common to locations such as Hawaii and west Africa, it remains uncommon in others, including the Mediterranean. In the places where L. guttatus is prevalent, it is not a target of fishing, though it does represent an important commercial component of bycatch. It is common in restaurants in Hawaii. In Hawaiian longline fisheries, it is generally caught on deep sets targeting big-eye tuna. In 2005, the fish caught numbered 13,332. In areas where the fish is uncommon, such as the Mediterranean, its prevalence is increasing. Some researchers believe this a result of climate change. Much is still unknown about the distribution, interactions, life histories, and preferred habitats of this fish and other medium to large-sized pelagic fishes.

In May 2015, it was shown to maintain its entire body core above ambient temperature, becoming the first known fish with this trait ('whole-body endothermy'). It can consistently keep its body core approximately 5 °C (9.0 °F) warmer than its environment.  So the question remains.  Is it an

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