Spot-fin porcupinefish

The spot-fin porcupinefish (Diodon hystrix), also known as the spotted porcupinefish, black-spotted porcupinefish or simply porcupinefish, is a member of the family Diodontidae.
In case of danger, the porcupinefish can inflate itself by swallowing water to deter the potential predator with its larger volume and it can raise its spines.
The porcupinefish concentrates tetrodotoxin, in certain parts of its body such as the liver, skin, gonads and the viscera. This defensive system constitutes an additional device to dissuade the potential predators.

There are reports that this species is toxic to humans