Also known as salema porgy or the sea bream, this fish is indigenous to the Eastern Atlantic and Mediterranean. Although the fish's flesh is safe to eat, psychoactive chemicals can accumulate in its head. Those who are brave or ethnic enough to consume this fish's head run the risk of ichthyoallyeinotoxism, a scientific term for "You just ate a fish head--welcome to 48 hours of mind-blowing hallucinations!"
Before you go down to your local fishmonger and start decapitating every fish in sight, know a couple of things. First, the fish's head is rarely psychotropic--the sarma salpa's hallucinogenic powers come from a compound called indole, which is present in the plankton and algae it eats. If there isn't enough indole, then you'll just be that sober, fish-head-eating person you see at every kegger.
Furthermore, tripping on the Sarpa Salpa is a magical mystery tour through the seventh circle of hell. Crippling terror, unearthly howls, and visions of demonic animals are reputedly common. In 1994, one salpa-tripping man realized something was terribly awry when giant arthropods surrounded his car.
Not an actual photo of incident
In 2006, medical journal Clinical Toxicology reported that ancient Romans knowingly hallucinated off of Sarpa Salpa heads. Presumably these bad fish trips inspired all that strange as hell Roman mythology, or at least the mass orgies.