Pufferfish, tobies, porcupinefish, boxfish and cowfish. Slow, poorly streamlined fish that have given up speed for a defence: a rigid box, a mouthful of water, or a toxin.
Almost all of them carry tetrodotoxin, which is not made by the fish but by bacteria it accumulates. There is no antidote. It matters if the fish is eaten and not otherwise: a puffer is safe to be near and safe to photograph.
Inflating is a last resort and it costs the fish. It is done by swallowing water, it takes time to reverse, and a fish made to do it for a photograph has been harmed for a picture that shows the animal doing something it does not normally do. The site does not carry photographs taken that way.
The boxfish and cowfish are a different defence: a rigid shell of fused plates, with only the fins, eyes and mouth free to move. They swim slowly and can be approached closely, and several release a toxin from the skin when stressed.
Every one has a page. They are shown as a list rather than as pictures because nothing has been photographed or logged for them yet, and a species with nothing behind it should not sit in front of one that has.
How many of the 23 carry a record at each destination. A species usually carries several, so these do not add up to 23.
All 1316 species in one index, with filters for destination, rarity and hazard.