Scientists have re-discovered one of the most strongly bioluminescent mushrooms known, 170 years after the first, and until now only, sighting of the species. Glowing fungi aren't all that unusual in nature, there are 71 known species. But "this one is incredibly bright for a luminescent mushroom," says Dennis Desjardin, a professor of evolutionary biology at San Francisco State University who researches fungi. "It glows more brightly than almost all other luminescent mushrooms." While most glowing fungi are either tiny or faint, these mushrooms emit a greenish light strong enough "that if you were in a dark room and you put one on a newspaper, you'd be able to read the words," says Desjardin.