Overview
The Ghost Fungus (Omphalotus nidiformis) is a spectacular bioluminescent gilled mushroom native to southern Australia. Resembling an oyster mushroom by day with its pale, funnel-shaped caps, this saprotrophic fungus undergoes a magical transformation once night falls, emitting an ethereal, continuous green glow from its gills. Visible to the naked eye after human vision adjusts to the dark, the ghost fungus is among the most famous and widespread glowing fungi in the Southern Hemisphere.
Biology and Physical Characteristics
Omphalotus nidiformis produces large, fan- or funnel-shaped caps that can span up to 12 inches across. By day, the upper cap surfaces are cream to buff-colored, often tinged with dark brown, purple, or slate-black centers. The bioluminescence originates from an oxidative enzymatic reaction within the gills: a specialized enzyme called luciferase catalyzes the oxidation of luciferin in the presence of oxygen, releasing excess metabolic energy as green light at a wavelength of approximately 530 nanometers.
Behavior and Ecology
As a white-rot wood decay fungus, Omphalotus nidiformis plays an indispensable ecological role in cycling nutrients within Australian eucalyptus ecosystems. Its subterranean mycelial network penetrates decaying stumps, dead roots, and the bases of living trees, degrading tough lignocellulose. While bioluminescence is energy-intensive, mycologists hypothesize that the nocturnally glowing gills attract nocturnal beetles, flies, and gnats, which walk across the fertile lamellae and disperse fungal spores across the forest floor.
Conservation and Human Impact
Evaluated as common and of Least Concern across its native range, the ghost fungus thrives in established national parks, state reserves, and urban nature strips across South Australia, Victoria, New South Wales, and Western Australia. While non-lethal, the fungus is poisonous to humans if ingested, containing illudin compounds that cause severe gastrointestinal distress. It remains a major ecotourism attraction, drawing nocturnal nature walkers to forest trails each autumn following soaking rains.
Interesting Factoid
The ghostly green light emitted by Omphalotus nidiformis does not switch off during the day: it glows continuously 24 hours a day, but can only be seen by human eyes in complete darkness!
Last updated: October 2026