The escolar, Lepidocybium flavobrunneum, is a species of fish in the family Gempylidae. It is found in deep (200–885 m) tropical and temperate waters around the world. It is also known as Snake Mackerel, and sometimes marketed as "butterfish" or "white tuna", a controversial practice due to potential health problems related with consumption of the fish.
Escolar is consumed in several European and Asian countries, as well as in the USA, sometimes raw as sushi or sashimi. It may be sold as "white tuna" - a term also used for the albacore - or as "super white tuna" to distinguish it from the albacore. Escolar is also sold misleadingly as "butterfish", "oilfish" and "Hawaiian butter fish"; in Fiji, it is known as Walu. Like oilfish, a related species with similar consumption consequences, escolar is also sometimes deceptively sold under the name of an entirely different species of fish, most commonly "codfish", "orange roughy" or "sea bass".
In 2009, as part of a project to create a DNA database of every fish species, scientists from Columbia University and the American Museum of Natural History tested tuna samples from sushi restaurants in New York City and Denver, Colorado. They discovered that five out of nine restaurants serving fish labeled “white tuna,” “white tuna (albacore)” or “super white tuna” were actually serving escolar.
Because of the possible effects of consumption, escolar has been banned from consumption in Japan since 1977, as the Japanese government considers it toxic. It has also been banned in Italy.
A Nova Southeastern University genetics class this semester tested fish advertised as white tuna from 10 sushi restaurants in Broward, Miami Dade and Palm Beach counties. The results showed eight were improperly labeled, said Professor Mahmood Shivji. A similar study last fall involving 10 restaurants in South Florida and Orlando, showed all 10 served escolar that was sold as white tuna.
A 2009 study, conducted by Columbia University and the American Museum of Natural History, found that 19 of 31 restaurants visited in New York and Colorado either misrepresented or were unable to clarify which species of fish they sold. Five out of nine samples sold as a variant of "white tuna" were actually escolar.