Gasutoro (ガストロ) is widely distributed throughout the temperate and subarctic regions of the Southern Hemisphere, but is not known to be found in the Northern Hemisphere. It is found in the open ocean around Australia and New Zealand, at depths of about 200 meters. It has the English name “Butterfly Tuna (Gasterochisma melampus Richardson, 1845)” because of its large, butterfly-like abdominal fins.
It is mostly caught as bycatch in longline fisheries that catch southern bluefin tuna. This is due to the overlap in habitat with southern bluefin tuna.
It is often thought to taste similar to tuna, a popular sashimi fish, perhaps due to the inclusion of maguro and tuna names in its name, such as “Uroko maguro” and “Butterfly tuna,” but it actually does not resemble tuna very much.
It has a refreshing flavor more like swordfish tuna. The best way to eat it raw is marinated with soy sauce, which takes about 15 minutes for the whole saku (fillet).
We hope this information will be helpful.
Revision date: January 28, 2023
Share this article