Scientists have discovered and formally identified six new species of mushrooms in the Pluteus podospileus group that was previously thought to be a single variable species across the Northern Hemisphere. Using DNA analysis combined with traditional microscopic examination, researchers found that what was once considered one widespread species is actually multiple distinct species with different geographic distributions in Europe, Asia, and North America. The study also resurrected an old, forgotten species name and clarified the relationships between various populations of these small brown mushrooms that grow on decaying wood in forests.