Psychedelic mushrooms growing in southern Africa have been identified as a new species that is the closest relative of Psilocybe cubensis, the most well-known magic mushroom species. The discovery brings scientists a step closer to understanding the evolutionary origins of these psychoactive fungi.
at Clark University in Worcester, Massachusetts, and his colleagues have named the newly described species Psilocybe ochraceocentrata, because of the ochre colour in the centre of the cap. It was collected from multiple sites across Zimbabwe and South Africa between 2013 and 2022.
There are around 160 wild species of Psilocybe mushrooms around the world that produce psilocybin, a chemical that induces psychedelic experiences. Researchers are investigating a range of possible therapeutic applications for psilocybin, including in treating depression and chronic pain.
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P. cubensis is widely cultivated all over the world and it grows wild in parts of the Americas, Asia and Australia, often in association with cattle dung.
P. ochraceocentrata is very similar in appearance, but genetic analysis showed that it is a distinct species. Bradshaw says P. cubensis and P. ochraceocentrata probably share a most recent common ancestor that lived around 1.5 million years ago.
Bradshaw and his colleagues think it is likely that this common ancestor evolved in Africa and spread to other parts of the world alongside large herbivores. 鈥淏oth these species are dung-loving, and while it鈥檚 impossible to state directly the factors that led to their speciation and movement, we suggested that they could have naturally followed the path of their herbivore dung producers,鈥� says Bradshaw.
Team member at the University of Utah, Salt Lake City, says the two species may have become isolated as the climate got drier. 鈥淎fter continuous habitat connecting Africa and Asia disappeared in the Middle East due to aridification, gene flow would have been cut off between the Asian and African populations, causing them to diverge,鈥� he says.
The team suggests P. cubensis may have migrated to the Americas alongside bison before the first people arrived. 鈥淭he current global distribution of P. cubensis alongside domesticated cattle is almost certainly due to inadvertent human introduction by cattle,鈥� says Dentinger.
In South Africa and Zimbabwe, psychedelic users seek out a variety of magic mushroom known locally as Natal Super Strength, which was thought to be a species called Psilocybe natalensis. However, the researchers found that many of the specimens they analysed were in fact the new species.
at Psymbiotika Lab in Brisbane, Australia, who has spent much of his career disentangling the origins of Australia鈥檚 wild Psilocybe mushrooms, says it remains to be proven that P. ochraceocentrata really is a new species.
鈥�P. ochraceocentrata is similar to P. cubensis in appearance, environmental niche and molecular barcode genes,鈥� says McTaggart. 鈥淎nd these criteria are becoming less reliable to distinguish species the more we understand fungal speciation.鈥�
A population scale analysis of gene flow, which would determine whether there is movement of genetic material between P. ochraceocentrata and P. cubensis, would provide confirmation, he says.
biorxiv
