Gymnopilus spectabilis

Scientific name: Gymnopilus spectabilis (Fries) Smith  
Derivation of name:  Spectabil- means "notable" or
"remarkable."
Synonyms:  
Common name(s): Big laughing Gym  
Phylum:   Basidiomycota
Order:   Agaricales
Family:   Cortinariaceae
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.

More information at MushroomExpert.com:  
More information at TomVolkFungi.net:


Figure 1. A cespitose cluster on wood. Photo © Dianna Smith.

Figure 2. Big laughing Gym on wood.
Photo © Pam Kaminski.

Figure 3. A specimen detached from its wood substrate.
Photo © Larry Grand.

Figure 4. Some years ago I found this cluster arising from
the center of a rotting stump near my home in central
Pennsylvania. I never saw such a large mushroom before.
Unfortunately, I also didn't know that much about
mushrooms. In hindsight, I've come to accept that it is
Gymnopilus spectabilis but I have no hard evidence, just
these pictures. Any other opinions?

Figure 5. Same mushroom as in Figure 4.

Figure 6. Same mushroom as in Figure 4.