This Mushroom Makes 90% of Users See Hundreds of Tiny People. Nobody Knows Why.
A mushroom from Yunnan, China makes nine out of ten people who eat it see hundreds of tiny, three-dimensionally rendered people crawling over the furniture. The compound responsible has never been identified.
Somewhere in the markets of Yunnan, China, vendors sell a prized edible bolete mushroom that comes with a peculiar side effect: roughly 90% of people who eat it spend the next several days watching miniature people, gnomes, clowns, and fairy-like figures crawl under doorways and climb across their furniture. The mushroom is called Lanmaoa asiatica, and according to ongoing research at the University of Utah, it may contain a psychoactive compound science has never seen before.
Lanmaoa asiatica reliably induces vivid Lilliputian hallucinations
Lilliputian hallucinations, named for the tiny inhabitants of Jonathan Swift's fictional island, are a clinically recognized syndrome in which a person perceives miniature human or humanoid figures in their external environment. They can arise from alcohol withdrawal, dementia, or Charles Bonnet syndrome, but studying them has historically been difficult because they occur unpredictably. Lanmaoa asiatica changes that equation.
The hallucinations it triggers are not vague or peripheral. As doctoral student Colin Domnauer of the University of Utah's Dentinger Lab described them: "These aren't like some vague hallucinations, these are like three-dimensionally-rendered, highly-detailed figures inhabiting your exterior world. And they're also interacting with objects in the real world, like crawling up chairs and tables or under doorways, people say." Effects begin 12 to 24 hours after ingestion and can persist for several days. The onset and duration are clinically distinct from classical serotonergic psychedelics like psilocybin, suggesting a fundamentally different mechanism is at work.
Locals in Yunnan have long treated the mushroom as an accidental novelty rather than a spiritual tool. The psychoactive effects are considered an undesirable side effect of what is otherwise a valued food source. Similar reports emerged from Papua New Guinea between the 1930s and 1960s, where Western observers dismissed the accounts as "mushroom madness" and moved on. Domnauer's work is the first systematic attempt to take those reports seriously.
A potential novel compound with no match in any known database
The most striking finding so far is what researchers have not found. Chemical screening and whole-genome sequencing of L. asiatica and closely related species have turned up no traces of psilocybin or any other known psychoactive compound. Analyses at the Natural History Museum of Utah confirmed that nothing in the mushroom's chemistry matches anything in existing databases.
"There weren't even any known psychoactive compounds, so it seemed like this must be some new hallucinogenic compound waiting to be discovered, because there's nothing that matches anything in our database," Domnauer said.
This is early, investigational research. No compound has been isolated or identified yet, and the behavioral changes observed in mice given L. asiatica extracts, hyperactivity followed by a stupor-like state, have not been confirmed to mirror human hallucinations. Hospital records from people who consumed the mushroom show zero deaths and no abnormalities in vital organ function, which is notable, but those records likely reflect only the cases serious enough to seek medical attention. The exact dose needed to produce hallucinations also remains unknown.
How Domnauer built a research tool out of ethnobiology
Domauer made tracking down this mushroom the central project of his PhD in the Dentinger Lab. He traveled to China and the northern Philippines, speaking with local communities that traditionally consume L. asiatica and collecting physical samples. DNA sequencing confirmed the mushrooms from both locations belonged to the same species, linking independent reports of its hallucinogenic properties across two countries.
The species was formally described to science only in 2015 by mycologists G. Wu and Zhu L. Yang, even though it had been sold in Yunnan markets for decades before anyone recognized it as its own taxon. It forms a mycorrhizal relationship with pine trees, meaning it cannot be cultivated artificially in a lab, which adds logistical complexity to every step of the research. Domnauer himself has not intentionally consumed the raw mushroom, citing the long and unpredictable duration of its effects and the unknown dosage.
The research pipeline now involves screening chemical fractions of the mushroom extract to narrow down which portion produces bioactive effects, then working toward isolating and identifying the specific molecule. University of Utah researchers exploring Lanmaoa asiatica's unique hallucinations have described this as a race to characterize a compound before the traditional knowledge surrounding it disappears entirely.
Why a novel psychedelic compound could matter beyond the hallucinations
If a genuinely new psychoactive molecule is isolated, the implications extend well beyond curiosity. A growing body of evidence links hallucinogenic compounds to therapeutic applications for conditions including PTSD, mood disorders, and substance use disorders, areas where existing treatments frequently fall short. A compound that produces effects through a pathway entirely separate from the serotonin system could open new avenues for both basic neuroscience and, eventually, clinical research.
The therapeutic potential of fungal psychedelics is already drawing serious attention, with researchers investigating fungal bioactives for depression, anxiety, and addiction. A compound that specifically triggers Lilliputian hallucinations would also give neuroscientists a reliable, reproducible tool to study why the brain generates those particular perceptions at all, a question that remains unanswered even for cases caused by alcohol withdrawal or dementia.
The race against deforestation and vanishing traditional knowledge
The research faces a deadline that has nothing to do with laboratory timelines. L. asiatica depends on pine forests for its survival, and deforestation in Yunnan is shrinking those habitats. At the same time, the traditional knowledge held by communities who have observed the mushroom's effects for generations is eroding as younger people leave rural areas. Domnauer's fieldwork is partly an act of conservation, documenting what locals know before that knowledge is gone.
The specific mushroom responsible for the Papua New Guinea reports from the mid-twentieth century has still not been identified, meaning one thread of this story remains entirely unresolved. Whether the compound, if found, will prove medically significant or simply scientifically fascinating is an open question. For now, the most honest summary is also the most intriguing: a fungus that reliably makes most people see tiny, detailed, interactive humanoid figures contains nothing science currently recognizes as a hallucinogen.
Evidence rating
INVESTIGATIONAL — 53/100
This article is a journalistic interview summarizing early-stage ethnomycological research into Lanmaoa asiatica, a bolete mushroom associated with Lilliputian hallucinations. The underlying science relies on hospital case-series data, mouse behavioral assays, and genomic screening; no controlled human trial has been conducted, and the causative psychoactive compound has not been isolated. The evidence is preliminary and not yet replicated under controlled conditions.
References
- Gang Wu, Kuan Zhao, Yan-Chun Li, et al. (2015). Four new genera of the fungal family Boletaceae. Fungal Diversity. https://doi.org/10.1007/s13225-015-0322-0
- Experts Explore New Mushroom Which Causes Fairytale-Like Hallucinations. nhmu.utah.edu. https://nhmu.utah.edu/articles/2025/11/fairytale-like-hallucinations
- The Hallucinogenic Mushroom That Makes You See Hundreds of Tiny People. nhmu.utah.edu. https://nhmu.utah.edu/articles/2025/12/lilliputian-mushrooms
- Clinical applications of hallucinogens: A review – PMC. NIH. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5001686/
- Elaine Meade, Sarah Hehir, Neil Rowan, Mary Garvey (2022). Mycotherapy: Potential of Fungal Bioactives for the Treatment of Mental Health Disorders and Morbidities of Chronic Pain. Journal of Fungi. https://doi.org/10.3390/jof8030290
