Psilocybe Subaeruginosa

Psilocybe subaeruginosa is a psychedelic mushroom of Australasia, which has psilocybin and psilocin as its main active compounds. 

First described in 1927 by Australian mycologist John Burton Cleland, it was previously placed in the section Cyanescens. 
Cyanescens has since been deprecated as a section and so Psilocybe subaeruginosa now falls under the section Semilanceatae.
Studies of comparative morphology, isozyme analysis and mating compatibility approaches have shown that P. australiana, P. eucalypta and P. tasmaniana are synonyms of this species. 
However, further studies have rejected the proposed synonymy with P. tasmaniana based on differences in habitat and microscopic characters.