Which tetraodontiform fishes have poisonous flesh?

Within the order Tetraodontiformes, the puffer fishes (family Tetraodontidae) are the primary group known to have poisonous flesh.1

It is important to note that while their flesh can be toxic—particularly during certain seasons—the majority of the highly potent neurotoxin responsible for fatalities, known as tetraodontoxin (or tetrodotoxin), is concentrated in the fish's viscera. Because of this danger, the consumption of these species is extremely hazardous and requires the expertise of highly trained professionals, such as the chefs who prepare fugu in Japan, to ensure the fish is cleaned and washed with absolute precision to remove the toxic organs.12

While these specific species pose a significant health risk, it is worth noting that the majority of other tetraodontiforms are considered palatable, with the flesh of various triggerfishes and trunkfishes being highly esteemed in many tropical regions.1