Wikipedia:Today's featured article/December 2, 2018

Marasmius rotula, the pinwheel mushroom, is a fungus in the family Marasmiaceae. Widespread in the Northern Hemisphere, it was first described scientifically in 1772 by mycologist Giovanni Antonio Scopoli. The mushrooms are characterized by thin whitish caps up to 2 cm wide that are sunken in the center and pleated with scalloped margins. The wiry black hollow stalks measure up to 8.0 cm long by 1.5 mm thick. On the underside of the caps are widely spaced white gills, attached to a collar encircling the stalk. The mushrooms grow in groups or clusters on decaying wood such as fallen twigs and sticks, moss-covered logs, and stumps. Spore release is dependent upon sufficient moisture. Dried mushrooms may revive after rehydrating and release spores for up to three weeks, much longer than most gilled mushrooms. Although the mushrooms are not generally considered edible, they produce a unique peroxidase enzyme that is attracting research interest for use in bioengineering applications.