Agaricus fuscofibrillosus
Family Agaricaceae · Updated October 2026
34US records
2states
Janbusiest month
34 US records since 1951 (0 in the last 10 years)
Last seen Dec 25, 2012 (about 14 years ago) near Moss Beach, San Mateo County, CA, a preserved specimen in University of California Santa Cruz Fungal Herbarium. Most US records come from California and Michigan, and the busiest months are Jan, Dec and Feb. (Data as of October 26, 2026; records can lag by weeks.)
⚠ Never eat a wild mushroom based on this site. We show where fungi have been recorded, nothing more. We never say any mushroom is edible or safe, and you shouldn't decide that from any website, app or photo. Many deadly mushrooms look like harmless ones. If someone may have eaten a wild mushroom, call Poison Control at 1-800-222-1222 right away.
Lookalike warning. Many mushrooms, including deadly ones, closely resemble each other, and the only reliable identification comes from an expert looking at the actual specimen (often with spore prints or microscopy). Never use a name, photo or record count on this page to decide what something is.
When it's recorded
Records by month, all years. Busiest: Jan, Dec, Feb.
Where it's recorded
| State | Records | Latest sighting |
|---|---|---|
| California | 31 | Dec 25, 2012 |
| Michigan | 3 | Aug 9, 1967 |
Top counties
- San Mateo County, CA (19) · latest Dec 25, 2012
- Monterey County, CA (7) · latest Jan 11, 1983
- San Francisco County, CA (3) · latest Feb 18, 1980
- Chippewa County, MI (2) · latest Aug 14, 1956
- Montmorency County, MI (1) · latest Aug 9, 1967
- Marin County, CA (1) · latest Dec 30, 1977
- Humboldt County, CA (1) · latest Dec 10, 1965
More on this species from GBIF.
Bring along
🍄
Regional mushroom field guideSee on Amazon🍄
Folding mushroom knife with brushSee on Amazon🍄
Wicker foraging basketSee on Amazon🍄
10x hand lens / loupeSee on Amazon🍄
Spore print paperSee on AmazonAs an Amazon Associate we earn from qualifying purchases.