Scientific name: Gymnopilus junonius (Fr.) P.D.
Derivation of name: Junonius refers to Juno, wife of
Jupiter; spectabil- (of the most recent synonym below)
means "notable" or
Synonyms: Gymnopilus spectabilis (Fries) Smith
Common name(s): Big laughing Gym
Occurrence on wood substrate: Saprobic; solitary but most
often in cespitose clusters on decaying wood such as conifer
and deciduous stumps and logs or on the ground from buried
wood; July through October.
Dimensions: Caps 5-18 cm wide; stipes 3-20 cm long and
1-3 cm thick.
Cap: Smooth or with minute scales; orange-yellow to ochre-
orange; sometimes with anise odor; bitter taste.
Gills: Attached to decurrent; pale yellow to rust.
Spore print: Rusty orange to rusty brown.
Stipe: Pale yellow to ochre; streaked with tiny fibrils.
Veil: Membranous to fibrous, typically leaving a superior ring
but sometimes just a ring zone on the stalk.
Edibility: Bitter, hallucinogenic.
Comments: Lincoff states that this species was named Big
Laughing Gym in Japan because its ingestion leads to
"unmotivated laughter and foolish behavior." Miller indicates
that the hallucinogens vary from one population of the
mushroom to another. This mushroom is probably more
widely known by its synonym, G. spectabilis.
More information at MushroomExpert.com:
More information at TomVolkFungi.net:
Figure 1. Some years ago I found this cluster arising from
the center of a large rotting stump near my home in central
Pennsylvania. I never saw such a large mushroom before.
Unfortunately, at that time, I didn't know that much about
mushrooms. No spore print was obtained and
mushroom was discarded. Based on its size and visible
features, I've come to believe that it's Gymnopilus
junonius but I have no firm evidence. Other opinions?
Photo © Gary
Figure 2. Same mushrooms as in Figure 1. The mushrooms
grew as a cespitose cluster. Photo © Gary
Figure 3. Same specimens as in Figures 1 and 2. The gills
are attached and there is a persistent ring high on the
Photo © Gary
Figure 4. A different specimen identified as the same
Photo © Larry Grand.