Scientists find the first mushroom known to make both the ‘magic mushroom’ drug and a deadly poison

A tiny brown mushroom from Florida is the first known to make both psilocybin, the drug in “magic mushrooms,” and amatoxins, the family of poisons that make death cap mushrooms deadly, University of Florida researchers reported Nov. 11 in the journal Current Biology.

Researchers nicknamed it the “dark magic mushroom.”  The finding means someone picking wild mushrooms to get high could swallow a poison instead, and the mushroom is very hard to tell apart from many look-alikes.  “It’s hard to differentiate from others, even for a trained expert,” said Matthew E. Smith, a plant pathology professor and Florida’s state mycologist, or mushroom expert.

Staying safe in California

The species, Galerina indica, was found in central Florida, not California.  But deadly mushrooms grow here, and the danger peaks in the rainy season.  Between Nov. 18, 2025, and Feb. 9, 2026, 40 people in California, including in the Bay Area, were poisoned by amatoxins from wild mushrooms, and four died, the San Francisco Department of Public Health said.  Cooking, boiling, drying or freezing does not destroy the poison, the department said.

The California Poison Control System says:

• Do not pick, cook or eat wild mushrooms, including ones friends or family picked.  Buy mushrooms only from established food markets.
• Poisonous mushrooms often look like edible ones and are not always brightly colored.  Symptoms usually start 6 to 12 hours after eating.
• If someone ate a wild mushroom and has severe vomiting, diarrhea or stomach pain, call 911, then the Poison Hotline at 1-800-222-1222.

What the scientists found

Andrew Kunik, then a researcher in Smith’s lab, found the mushroom on moss-covered palm trunks in a wetland.  It bruised blue when handled, a sign of psilocybin, but belonged to a group, Galerina, known for amatoxins.  Chemical tests found both kinds of compounds, and a reading of the mushroom’s full DNA found genes for making both, the researchers reported.

Amatoxins kill by shutting down a basic machine inside cells, which can destroy the liver.  Psilocybin is a federally banned drug that causes hallucinations and is being studied as a mental-health treatment.  Mushrooms normally make one or the other.  The researchers think the mushroom’s ancestors picked up the genes by swapping DNA with other species, a process called horizontal gene transfer.

The study measured which chemicals the mushroom makes; it did not test how much of the mushroom would harm a person.  Scientists still don’t know why mushrooms make either compound.  One idea is that the poisons defend mushrooms from animals that eat them, the university said.

Source:  University of Florida announcement, Nov. 11, 2026; *Nature* research highlight, Nov. 12, 2026; California Poison Control System:  Wild Mushrooms; San Francisco Department of Public Health advisory; researchers’ preprint (PMC).