Pileus (Cap): 8 cm, thick, convex with a large umbo, ochraceous, dry, with conspicuous light reddish brown scales that are sparse but become denser toward the center; flesh firm, becoming green-spotted where handled.
Lamellae (Gills): Adnate, broad, crowded, edges undulate, dingy brown to rusty brown with age. Stipe (Stem): 6 cm x 2 cm thick, enlarging below, solid, firm, colored like the cap. Microscopic features: Spores Reddish Brown (6)7 x 8.5 x (3.5)4 - 5 um ellipsoid, not dextrinoid, minutely verruculose, obliquely pointed at one end, no germ pore. Pleurocystidia absent, Cheilocystidia 20 - 26 x 5 - 7 um, caulocystidia 35 - 43 x 4 - 7 um, clamp connections present.
Season: October to November.
Habitat and Distribution: Gymnopilus viridans is found on coniferous wood. Washington.
Growth Habit: Gregarious to cespitose.
Bruising: Green or blue bruising at the base and on the pileus, green spots on the pileus likely.