It's something you would never expect to go missing, but one of the world's brightest glow-in-the-dark mushrooms has been rediscovered after an absence of more than 170 years, according to USA Today.

The bioluminescent shrooms had become a Brazilian legend of sorts. They were first spied in 1840 by an English botanist named George Gardner, who was alarmed after he saw some boys playing with a glowing object in the streets of Vila de Natividad, a village in the Goiás state in central Brazil. After that, no more sightings of the brightly glowing fungus had ever been reported.

The mushroom was nearly forgotten until 2002, when Brazilian chemist Cassius Stevani came across Gardner's early reports. Then, in 2005, a breakthrough occurred. A pair of primatologists, Patricia Izar from São Paulo University in Brazil and Dorothy Fragaszy of the University of Georgia in Athens, were studying a band of monkeys deep in the Brazilian interior when they came across something mysterious glowing at the base of some palm trees.

Izar and Fragaszy scooped up specimens and contacted Stevani, who later confirmed that the mushrooms were indeed Gardner's long lost species. The findings are what led to this month's paper in the journal Mycologia.

Ironically, right after the rediscovery of the mushrooms, scientists came to learn that local people were quite familiar with them. In fact, the mushrooms had a common name, flor-de-coco, or flower of the coconut, since it is commonly found on the rotting fronts of dwarf palm trees. As is often the case, scientists had just never bothered to ask.

Although glowing fungi are nothing new to science — there are 71 identified species — this particular species (named Neonothopanus gardneri, after the initial discoverer) is notable for its size and the extraordinary strength of its light.

"It glows more brightly than almost all other luminescent mushrooms," said Dennis Desjardin, a fungi expert at San Francisco State University. "If you were in a dark room and you put one on a newspaper, you'd be able to read the words."

Desjardin also noted that these mushrooms can grow up to three inches in diameter, which is giant compared to most bioluminescent fungi.

Stevani is currently working to identify the chemical pathways that allow these mushrooms to produce light, a system that remain a mystery to science. As for why they glow, scientists still aren't sure why it happens. One theory suggests that the mushrooms may glow to attract insects that help to spread their spores. Another theory, also involving the attraction of insects, proposes that the light is a beacon to predatory bugs that feed on insects that threaten the fungus.

One thing researchers are certain of, however, is that these mushrooms are poisonous. So while the mushrooms' glow-in-the-dark properties may be interesting to people, researchers strongly advise that they shouldn't be eaten.

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