Florida’s ‘dark magic mushroom’ makes both psilocybin and death cap toxins

A little brown mushroom that grows on rotting palm trunks in Florida’s wetlands makes two kinds of chemicals that were never supposed to share a body. One is psilocybin, the psychedelic compound in magic mushrooms. The other is a pair of amatoxins, the same family of poisons behind most fatal mushroom poisonings worldwide.

The species is Galerina indica, now nicknamed the “dark magic mushroom” by the University of Florida team that analysed it. It also turns blue when handled, the colour change many people read as the signature of a psychedelic species, so in this mushroom that cue sits on top of a liver-wrecking toxin family. “There is no species of mushroom anywhere, in any group, that has been known to produce both at the same time,” first author Andrew Kunik told Live Science. “So it’s quite remarkable.”

Psilocybin and amatoxins each turn up in several unrelated groups of fungi, because the genes for both have jumped between species by horizontal gene transfer, in which DNA moves sideways between organisms instead of passing from parent to offspring. Until this study, published in the journal Current Biology, no single species was known to carry both toolkits.

A hunt for poison turned up a psychedelic

The team wanted to know whether Florida’s understudied Galerina mushrooms included unrecorded deadly species. The genus already holds the toxic Galerina marginata group, known as “funeral bells”, and senior author Matthew E. Smith is Florida’s state mycologist, the person poison control and emergency doctors call when someone may have eaten a wild mushroom.

Kunik, then an undergraduate in Smith’s lab, found an unusual specimen while documenting fungi at the university’s Ordway Swisher Biological Station. It looked like a common Galerina, but it stained blue. The researchers collected five Galerina specimens across the southeastern United States. Three, all taken from moss-covered palm trunks in forested wetlands, were G. indica. The largest was only about half a centimetre tall, according to Live Science.

Mass spectrometry, which sorts molecules by weight and fragments them to read their structure, was run against certified reference samples. Every G. indica sample contained psilocybin and its close relative psilocin, plus two amatoxins. The main one was new to science, and the team named it alpha-proamanitin. It is identical to alpha-amanitin, the classic killer in death cap mushrooms, except that it lacks a single oxygen-hydrogen group on one of its building blocks. Alpha-amanitin itself never showed up. The team then repeated the whole analysis with fresh tissue and control mushrooms of known chemistry.

Two gene jumps built one mushroom

To learn how the mushroom got its double arsenal, the team sequenced its genome and found all five genes that make up the standard psilocybin assembly line, plus a compact amatoxin gene cluster laid out like the one in the deadly funeral bells.

The two pathways tell different stories. The amatoxin genes of G. indica group tightly with those of its toxic relatives, which points to a single arrival of amatoxins in Galerina long ago. The psilocybin genes do not group with anything in Galerina. A second, unnamed Galerina from Mississippi makes psilocybin but no amatoxins, and its five genes sit in a different order from those in G. indica. Distinct gene orders are a fingerprint of separate acquisitions, so the authors conclude the psilocybin cluster jumped into the genus at least twice. Two separate arrivals explain the pattern with no losses at all, against roughly a dozen losses if the genes had been there from the start.

In the branch of the family tree that holds G. indica, the poison came first and the psychedelic arrived later. Smith told Live Science the psilocybin genes likely came in about 15.5 million years ago, while Kunik noted they may have entered in two separate events, possibly as recently as 6 million years ago. “To find them both together in one mushroom, I never expected to find that,” Smith said. “We were shocked.”

Why the blue test breaks down

Psilocybin mushrooms bruise blue because psilocin, the compound psilocybin turns into, forms blue-coloured chains when the tissue is damaged. People who pick wild mushrooms often treat that blueing as a way to separate psychedelic species from toxic look-alikes growing nearby. The authors write that the cue may only be reliable in well-known, cultivated magic mushrooms with a history of human use, such as Psilocybe cubensis, because G. indica shows blueing and amatoxins together.

The stakes come from the toxin family. Amatoxins block RNA polymerase II, the enzyme every animal cell needs to read its own genes, and the damage leads to organ failure. They cause most fatal mushroom poisonings, and the death cap, Amanita phalloides, is their best-known source.

“These mushrooms are really hard to find. They are small and brown, like hundreds of other mushroom species,” Smith said in the university’s release. “It’s hard to differentiate from others, even for a trained expert.”

What the study doesn’t settle

The first open question is how dangerous the dark magic mushroom actually is. Alpha-proamanitin lacks the hydroxylated proline that helps amatoxins grip RNA polymerase II, and in lab tests amatoxins without it block the enzyme more weakly. The authors write that alpha-proamanitin “may be less bioactive” than alpha-amanitin, while stressing that amatoxins lacking that group remain toxic. The study did not test the mushroom’s toxicity in animals, so its real poison strength is unmeasured.

The sample is small. The chemistry rests on three G. indica collections from Florida, and the genome on one of them. Whether every population carries both pathways is unknown.

Nor does the paper explain why one mushroom would make both compounds. The leading idea is a stacked defence, similar to milkweed plants that combine toxins or crops engineered with two insecticidal proteins, where an attacker that adapts to one weapon still meets the other. Lab studies show nematodes and fruit flies can evolve resistance to amatoxins, and psychedelic compounds are also toxic to nematodes. That remains a hypothesis. The authors also float the reverse story: the arrival of psilocybin may have relaxed the pressure to keep making full-strength alpha-amanitin.

Hannah Reynolds, a fungal ecologist at Western Connecticut State University who was not involved in the work, called the genetic history the most striking part. “What was exciting about this paper was seeing both of these present, seeing that this gene cluster jumped in, got rearranged, maybe came in twice,” Reynolds told Live Science.

Common questions about the dark magic mushroom

What is the dark magic mushroom?

It is Galerina indica, a tiny brown mushroom that grows on moss-covered palm trunks in Florida’s wetlands. University of Florida researchers gave it the nickname after showing it is the first known species to produce both psilocybin and amatoxins.

Is the dark magic mushroom poisonous?

It contains amatoxins, the toxin family responsible for most fatal mushroom poisonings. Its main amatoxin, alpha-proamanitin, may be weaker than the alpha-amanitin found in death caps, but amatoxins of that type are still toxic, and the mushroom’s danger to people has not been measured.

Does a mushroom that turns blue mean it is a safe psychedelic species?

No. Blueing comes from psilocin, but G. indica turns blue and also carries amatoxins. The study’s authors say the blue cue may only hold for well-known cultivated species such as Psilocybe cubensis.

How did one mushroom end up with both compounds?

Through horizontal gene transfer. The amatoxin genes arrived in the Galerina genus once, and the psilocybin gene cluster jumped in later, at least twice, from distantly related psychedelic fungi.

What comes next

Kunik first spotted the mushroom in 2025, the team posted its findings as a preprint in July 2026, and the peer-reviewed paper appeared in Current Biology on November 11, 2026. The next step the team describes is to knock out the genes for one compound or the other and watch how the mushroom fares, a direct test of what each chemical does in the wild. Collecting and sequencing more Galerina, including the rarely seen relatives G. salicicola and G. minor, should show whether the psilocybin genes arrived once or twice in this lineage.

Kunik, now a postbaccalaureate researcher at Harvard, put the lesson in one line: “What’s exciting is that there are small, seemingly uninteresting fungi that can conceal extraordinary chemistry that we’re only beginning to understand.”

Reference: Kunik et al., “The ‘dark magic mushroom’ co-produces amatoxins and psilocybin,” Current Biology, 2026. DOI: 10.1016/j.cub.2026.10.041

Tags: biology, amatoxins, Galerina indica, magic mushrooms, poisonous mushrooms, psilocybin