Psilocybe tampanensis is a very rare psychedelic mushroom whose only known natural specimen was collected in the wild by Steven Pollock, near Tampa, Florida in 1977. All spores and cultivations of this species nowadays are originated from this only specimen. It has never again been seen in Florida but a second sighting was reported from Mississippi, however no culturable material was obtained. Psilocybe tampanensis forms psychoactive sclerotia that are known under the nickname Philosopher's stone.