Agaricus diminutivus

Agaricus diminutivus
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Agaricales
Family:	Agaricaceae
Genus:	Agaricus
Species:	A. diminutivus
Binomial name
Agaricus diminutivus Peck

Agaricus diminutivus Mycological characteristics
	Gills on hymenium
	Cap is ovate or flat
	Hymenium is free
	Stipe has a ring or is bare
	Spore print is brown
	Edibility is not recommended

Agaricus diminutivus, commonly known as the diminutive agaricus, ^[1] is a species of mushroom in the genus Agaricus . It is unique among its genus due to its small size, ^{[1] [2]} and was first described in 1873. ^[3]

Description

The cap of Agaricus diminutivus is about 1-3 centimeters in diameter. It starts out round or ovoid, becoming convex or flat. It is pale, often being whitish or tannish. ^[2] The stipe is 2-6 centimeters long and 3-10 millimeters wide, with a ring around it that sometimes disappears. ^[1] The gills are free, and start out a pale pinkish tan color becoming pink and finally brown. The mushroom's flesh both bruises slightly yellow and turns yellow when potassium hydroxide (KOH) is applied. ^[2] The spore print is brown. ^[1]

While likely edible, this mushroom is not recommended as food because it can be confused with poisonous Inocybe species. ^{[1] [4]} It is also very small and not very common. ^{[2] [3]}

Agaricus diminutivus is actually a species complex, consisting of multiple closely related species that are difficult to distinguish from one another. ^{[1] [2]}

Habitat and ecology

Agaricus diminutivus grows in forests, especially under conifers. It fruits during autumn. ^[2]

References

1. Arora, David (January 1, 1986). Mushrooms Demystified: A Comprehensive Guide to the Fleshy Fungi (2nd ed.). Berkeley, CA: Ten Speed Press. pp. 340–341. ISBN   9780898151695.
2. Siegel, Noah; Schwartz, Christian (September 1, 2024). Mushrooms of Cascadia: A Comprehensive Guide to Fungi of the Pacific Northwest. Humboldt County, California: Backcountry Press. p. 78. ISBN   9781941624197.
3. Stevens, Michael Wood & Fred. "California Fungi: Agaricus diminutivus". www.mykoweb.com. Retrieved 2025-07-15.
4. "E-Flora BC Atlas Page". linnet.geog.ubc.ca. Archived from the original on 2025-02-11. Retrieved 2025-07-15.