Swai is a fish from the Pangasius family and is similar to catfish. It's described as a river-farmed catfish, sometimes simply referred to in the U.S. as just "catfish." Swai fish are native to Southeast Asia, specifically Vietnam, Thailand, Laos and Cambodia.
Swai is a white-flesh fish with a sweet, mild taste and light flaky texture. Swai fish have fins that are either black or dark grey in color. Juveniles come with two black stripes, one along the lateral line and the other one just below it. They have shiny, iridescent skin, which is why they are also referred to as iridescent sharks.