Gymnopilus junonius

*Gymnopilus junonius*
Mycological characteristics
Gymnopilus junonius Mycological characteristics
	Gills on hymenium
	Cap is convex
	Hymenium is adnate
	Stipe has a ring
	Spore print is reddish-brown
	Ecology is saprotrophic
	Edibility is inedible

Gymnopilus junonius
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Agaricales
Family:	Hymenogastraceae
Genus:	Gymnopilus
Species:	G. junonius
Binomial name
	Gymnopilus junonius; (Fr.) P.D.Orton (1960)
	Approximate range of Gymnopilus junonius
Synonyms
	Agaricus aureus Bull. (1782); Agaricus junonius Fr. (1821); Lepiota aurea Gray (1821); Pholiota junonia (Fr.) P.Karst. (1879); Pholiota grandis Rea (1903); Pholiota spectabilis var. junonia (Fr.) J.E.Lange (1940); Gymnopilus spectabilis var. junonius (Fr.) Kühner & Romagn. (1953);

Gymnopilus junonius is a type of mushroom-forming fungus in the family Hymenogastraceae. Commonly known as the spectacular rustgill, this large orange mushroom is typically found growing on tree stumps, logs, or tree bases. Some subspecies of this mushroom contain the neurotoxic oligoisoprenoid gymnopilin.

Description

The cap ranges from 8–30 cm (3–12 in) across, is convex to flat,^[1] and is bright yellow-orange in younger specimens and orange-brown or reddish brown in older ones, with a dry scaly surface. The flesh is yellow, the odor mild and taste bitter.^[1] The stem is 5–25 cm (2–10 in) long, 1–5 cm thick, and often narrows near the base.^[1] The frail ring is dusted with rusty orange spores, and the gill attachment to the stem is adnate to sub-decurrent.^[1] It stains red with KOH and turns green when cooked. The spore print is rusty orange. Unlike psychoactive relatives in the Psilocybe genus, G. junonius lacks psilocybin and does not stain blue, but smaller specimens occasionally exhibit bruising.^[2] This mushroom usually grows in clusters from several to several dozen individuals, but sometimes grows solitary. It is inedible due to its bitter taste.

Similar species

This mushroom is often mistaken for Gymnopilus ventricosus, which also contains no psilocybin and G. luteus and G. subspectabilis, which do.^{[citation needed]} It also resembles Armillaria mellea and Omphalotus olivascens.^[1]

Distribution and habitat

Gymnopilus junonius is found in Europe, Australasia and South America.^[3]^[4]^[5] It grows in dense clusters on stumps and logs of hardwoods and conifers. This mushroom is most common in moist, lowland wooded areas near rivers.

This species does not occur in North America; however some similar looking species do. These include Gymnopilus ventricosus on the west coast and G. luteus and G. subspectabilis in the midwest and east.^[6]

Biochemistry

This mushroom contains bis-noryangonin and hispidin, which are structurally related to alpha-pyrones found in kava.^[7] Neurotoxins known as oligoisoprenoids have also been found in this species.^[8]

References

^ ^a ^b ^c ^d ^e Davis, R. Michael; Sommer, Robert; Menge, John A. (2012). Field Guide to Mushrooms of Western North America. Berkeley: University of California Press. pp. 245–246. ISBN 978-0-520-95360-4. OCLC 797915861.
^ Thorn, R. Greg; Malloch, David W.; Saar, Irja; Lamoureux, Yves; Nagasawa, Eiji; Redhead, Scott A.; Margaritescu, Simona; Moncalvo, Jean-Marc (2020-04-24). "New species in the Gymnopilus junonius group (Basidiomycota: Agaricales)". Botany. 98 (6). Canadian Science Publishing: 293–315. doi:10.1139/cjb-2020-0006. ISSN 1916-2790.
^ "Big Laughing Jim/Scientific Name: Gymnopilus junonius (formerly G. spectabilis)". Missouri Department of Conservation (nature.mdc.mo.gov). Archived from the original on 2021-01-04. Retrieved 2020-09-27.
^ "Earth Notes: The Laughing Jim Mushroom". www.knau.org. 31 January 2018. Archived from the original on 2021-01-04. Retrieved 2020-09-27.
^ "Gymnopilus junonius (Fr.) P. D. Orton - Spectacular Rustgill". www.first-nature.com. Archived from the original on 2021-01-04. Retrieved 2020-09-27.
^ "New species in the Gymnopilus junonius group (Basidiomycota: Agaricales)" (PDF). Retrieved 2022-03-28.
^ Hatfield, G.M.; Brady, L.R. (1969). "Occurrence of bis-noryangonin in Gymnopilus spectabilis". Journal of Pharmaceutical Sciences. 58 (10): 1298–1299. doi:10.1002/jps.2600581039. PMID 5388695.
^ Tanaka, Masayasu; Hashimoto, Kimiko; Okunoa, Toshikatsu; Shirahama, Haruhisa (1993). "Neurotoxic oligoisoprenoids of the hallucinogenic mushroom, Gymnopilus spectabilis". Phytochemistry. 34 (3): 661–664. Bibcode:1993PChem..34..661T. doi:10.1016/0031-9422(93)85335-O.