The fruit bodies, or mushrooms, have conic to bell-shaped to convex caps that are initially dark brown but fade to brownish-gray when young, reaching diameters of up to 4 cm (1+1⁄2 in).

The saprobic fungus is found in Europe and North America, where it grows in groups or clusters on the rotting wood of both hardwoods and conifers.

The cap margin closely approaches the stem when young, but often flares or curves upward with age.

It is cartilaginous and firm, dark or pale watery gray, changing slowly to dirty reddish-brown when cut or bruised.

They are narrow, becoming moderately broad (4–5 mm), whitish to pale gray in color, soon staining with reddish spots.

The stem is densely covered with sharp, stiff white hairs on the lower portion, and smooth above.

The stem base becomes stained reddish-brown to purplish, or the entire lower portion turns a dirty wine red.

The spores are white, ellipsoid,[8] amyloid (meaning they turn bluish-black to black when stained with Melzer's reagent), and measure 7–9 by 4–5 μm.

[12] In the absence of the characteristic reddish staining (particularly in young specimens), M. maculata is indistinguishable in the field from M. galericulata, which also tends to grow in groups or tufts on wood.

[9] Another Mycena that stains reddish is M. inclinata; it can be distinguished by its slightly larger spores, typically 7–9 by 5–6.5 μm, and the white flecks that develop on the lower part of the stem.

[15] The fruit bodies of M. maculata grow in groups to clumps on the wood and debris of both coniferous and deciduous trees.