Gymnopilus ventricosus
Gymnopilus ventricosus, commonly known as the jumbo gym or western jumbo gym, is a species of mushroom in the family Hymenogastraceae. It was first described from the Stanford University campus by Franklin [Sumner Earle] as Pholiota ventricosa in 1902.
Description
The cap is or larger in diameter, bright yellow-orange to rusty orange, covered with minute yellow hairs, sometimes becoming scaly. The flesh is thick, yellow and bitter. The gills are yellow to rusty orange, close, adnate to slightly decurrent. The stipe is 7-21 cm long, 1-4 cm thick, yellow-orange, streaked with brown fibrils, club-shaped or ventricose, usually narrowed at the base; partial veil yellowish, forming a superior membranous ring. White mycelium at the base of the stipe.Spores are ellipsoid or ovoid, warty, 7.5–9 x 4–5.5μm. The spore print is rusty brown to rusty orange. Clamp connections are present.
This species contains no psilocybin, and is considered inedible; it is very bitter.