Poisonous Fish in the world

 Puffer fish :

         Pufferfish can inflate into a ball shape to evade predators. Also known as blowfish, these clumsy swimmers fill their elastic stomachs with huge amounts of water (and sometimes air) and blow themselves up to several times their normal size. Some species also have spines on their skin to ward off predators. 

Spotted trunkfish:

               The spotted trunkfish (Lactophrys bicaudalis) is a member of the family Ostraciidae. It can be found in reefs throughout the Caribbean, as well as the south eastern Atlantic Ocean. The species gets its name from the black spots it has covered over its yellow-golden body.

Giant moray 

                The  giant moray (Gymnothorax javanicus) is the largest moray eel in terms of mass. An adult has a formidable set of rear facing teeth to go with its proportionally large mouth. As can be seen in the images, not only do they have teeth around the jaw, they have extra teeth on the roof of the mouth.

Sources : Wikipedia & Goolge