Basa ("Pangasius bocourti"), as it is commonly referred to, is a species of primarily freshwater-dwelling catfish in the shark-catfish family, Pangasiidae, native to the Mekong and Chao Phraya river basins of Mainland Southeast Asia.

[8] Other, related shark-catfish species may occasionally be labeled—albeit incorrectly—as basa, including the iridescent shark (P. hypophthalmus) and the yellowtail catfish (P. pangasius).

However, Mississippi State University researchers found imported basa were preferred three-to-one to US catfish in a small (58 testers) blind taste test.

It is mainly sold by large supermarkets, in both fresh and frozen forms, as a cheaper alternative to popular white fish such as cod or haddock.

[15] The import of basa is subject to the same stringent EU regulations as other food imports, as set out in the CBI pangasius product fact sheet[16] UK Trading Standards officers said that cobbler was being fraudulently sold as cod by some fish-and-chip retailers to take advantage of the much lower price of cobbler, which was about half that of cod.

[21] Testing by the Australian Quarantine and Inspection Service found trace levels of malachite green, but no other contaminants; this was likely the result of antiparasitic treatment administered to the fish, such as in the treatment of ich (white-spot disease), a common affliction of captive fishes with which malachite green (or methylene blue) is often remedied.