Monogr. Hym. Sueciae II:347.1863.
Common Name: none
Cap 2-6 cm broad, convex, broadly so to nearly plane in age, sometimes with a low umbo; margin at first incurved, then decurved, finally either plane or slightly raised; ground color cream-buff covered with vinaceous-brown to buff-brown appressed squamules or fibrils concentrated near the disc, diffuse towards the margin; surface bruising yellowish, eventually orange-brown, yellowing in KOH; flesh white to pallid, soft, thin; odor and taste of anise.
Gills free, close, moderately broad, at first cream, becoming light brown, at maturity dark-brown.
Stipe 3-7 cm tall 0.4-0.8 cm thick, round, stuffed, equal to tapering to an enlarged base; surface silky to finely longitudinally striate at the apex, elsewhere smooth or with scattered fibrils and scales, conspicuous rhizomorphs at the base; color white to cream, bruising yellowish to tawny-brown; veil membranous, thin, forming a narrow, fragile, buff to light-brown, superior ring, occasionally leaving fragments on the young cap.
Spores 4.5-5.5 x 3-3.5 µm, elliptical, smooth, thick-walled; spore print dark brown.
Solitary to gregarious in forest litter.
Edible, but unsubstantial.
This woodland Agaricus is recognized by its modest-sized, anise-odor, cap with vinaceous to brown appressed fibrils/squamules concentrated near the disc, and yellow to tawny bruising reaction. Other anise-odored, forest-dwelling Agaricus species include Agaricus silvicola, which is larger, cream-colored with a smooth cap and Agaricus diminutivus, a smaller, more slender, mushroom which usually lacks an umbonate cap. Another look-alike is Agaricus micromegathus, a rare, grassland species, also smaller, but otherwise similar.
Breitenbach, J. & Kränzlin, F. (1991). Fungi of Switzerland. Volume 3: Boletes and Agarics (1st Part). Strobilomycetaceae, Boletaceae, Paxillaceae, Gomphidiaceae, Hygrophoraceae, Tricholomataceae, Polyporaceae (lamellate). Verlag Mykologia: Luzern, Switzerland. 361 p.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Kerrigan, R.W. (1986). The Agaricales (Gilled Fungi) of California. 6. Agaricaceae. Mad River Press: Eureka, CA. 62 p.
Kerrigan, R.W. (2016). Agaricus of North America. New York Botanical Garden: Bronx, NY. 574 p.