Group D - Gilled fungi with a central to eccentric stem, no annulus,
even gill edges, attached or free gills, and purple-brown to black spores

1. Spore print purple brown

    2. Cap yellowish or brick-red

        3. Cap yellowish; gills yellow, then greenish, then tinted purple-brown
            when mature...................................................................................Hypholoma fasciculare

        3. Cap brick-red; gills whitish, becoming purplish-gray at maturity .......Hypholoma lateritium

    2. Cap white or creamy to light brown to dark brown

        4. Cap distinctly radially wrinkled, brownish fading to tawny; stipe greater than
            6 mm thick at the apex ......................................................................... Psathyrella rugocephala

        4. Cap smooth, without distinct radial wrinkling; stipe less than 6 mm thick at apex

            5. Cap dark brown fading to tan; often occurring in dense, cespitose clusters.......... Psathyrella hydrophila

            5. Cap creamy white to honey-brown; occurring single to scattered to numerous......Psathyrella candolleana

1. Spore print black

    6. Stalks arising from a yellow-orange mat of mycelium on the wood............................Coprinellus radians

    6. Stalks not arising from a mat of yellow-orange mycelium

        7. Cap 0.5-2.0 cm wide; stipes 0.5-2 mm thick..................................................Coprinellus disseminatus

        7. Cap and stipe with larger dimensions than above      

            8. Cap gray-brown, 5-7.5 cm wide; stalk 1-2 cm thick at apex; gills inky......Coprinopsis atramentaria
                Note: a membrane-like, fibrous ring may be present near the stalk base.         

            8. Cap tawny-brown, 2.5-5 cm wide, with mica-like granules at first;
                stalk 3-5 mm at apex, gills somewhat inky...................................................Coprinellus micaceus