Coprinellus micaceus is a common species of mushroom-forming fungus in the family Psathyrellaceae with a cosmopolitan distribution. The fruit bodies of the saprobe typically grow in clusters on or near rotting hardwood tree stumps or underground tree roots. Depending on their stage of development, the tawny-brown mushroom caps may range in shape from oval to bell-shaped to convex, and reach diameters up to 3 cm (1+1⁄4 in). The caps, marked with fine radial or linear grooves that extend nearly to the center, rest atop whitish stipes up to 10 cm (4 in) long. In young specimens, the entire cap surface is coated with a fine layer of reflective mica-like cells that provide the inspiration for both the mushroom's species name and the common names mica cap, shiny cap, and glistening inky cap. Alt