Glow-in-the-Dark Mushroom.

The arrival of rainy season in Wakayama Prefecture, Japan is marked by the appearance of the mysterious, glow-in-the-dark mushroom.

The Mycena lux-coeli mushrooms, known locally as shii no tomobishi-dake (literally, “chinquapin glow mushrooms”), sprout from fallen chinquapin trees. As they grow, a chemical reaction involving luciferin (a light-emitting pigment contained within the mushrooms) occurs, causing them to glow a ghostly green.

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