Biologist Colin Domnauer has revived a decades‑old mystery from Yunnan province, where summer hospital admissions spike with reports of tiny elf‑like figures marching through rooms. Chinese officials once traced the episodes to a locally prized mushroom, Lanmaoa asiatica, known for its umami flavor and the need to cook it thoroughly. The fungus induces a specific type of lilliputian hallucination that appears identical in different sufferers globally.

Domnauer surveyed Yunnan’s mushroom markets, asking vendors which species produced the visions; every stall pointed to L. asiatica. Genetic sequencing confirmed the identification, and laboratory extracts provoked dramatic behavioral changes in mice. He later located the same fungus in the Philippines, despite morphological differences, suggesting the hallucinogenic trait spans a broader geographic range than previously documented.

The hallucinogen is not psilocybin; onset takes 12 to 24 hours and episodes can persist long enough to require hospitalization, making the mushroom unsuitable for recreational use. Researchers hope that isolating the responsible compound could illuminate mechanisms behind shared visual hallucinations and offer new probes for studying consciousness and certain brain disorders and could lead to novel therapeutic targets.