About 25 years ago, researchers discovered that an Armillaria gallica mushroom near Crystal Falls, Michigan, covered about 91 acres, weighed 110 tons and was about 1,500 years old, setting a new record for the largest organism at the time. For a new study published on the preprint service bioRxiv, James Anderson, a biologist at the University of Toronto and one of the original discoverers of the fungus, returned to the site and took 245 samples from the mushroom and examined its genome. The team confirmed that indeed, the entire fungus is just one individual.
The DNA also showed a very slow mutation rate, meaning that the honey mushroom isn’t evolving very quickly. The visit also led them to revise the fungus’s age to 2,500 years and determine that it is four times as massive as the original estimate, or about 440 tons, the equivalent of three blue whales.
The Crystal Falls humongous fungus was the original humongous fungus that showed these organisms can reach massive size. But since its discovery it has been eclipsed by other honey mushrooms. An Armillaria found in eastern Oregon’s Blue Mountains covers three square miles and may be over 8,000 years old, holding the current title for humongous-est of the funguses.
https://www.smithsonianmag.com/smart-news/mushroom-massive-three-blue-whales-180970549/