I once went into a few local restaurants to surreptitiously test the tuna they served. Some tuna was tuna, some was grouper, some was Nile perch, but all of it looked the same when cooked. In many cases this is not a case of restaurants misleading customers, or even being mislead themselves, but simply a problem with the length of the supply chain. The more intermediates that a piece of fish has to go through to get from the boat to your table, the more chances there are for it to be misidentified.
Found on the shelf or coastal pelagic on various bottoms (sand, mud, rocks and seaweeds). Gregarious, ascending to the surface mainly at night. Omnivorous, feeding mainly on crustaceans, also planktophagous. Hermaphroditic, generally protogynous.