Inocybe pudica Kühner
Ann. Sci. Franche-Comté 2: 26. 1947.
Common Name: none
Cap 2.0-4.0 (5.0) cm broad, at first obtuse-conic, then convex, to convex-umbonate, expanding to plano-convex, often with a low umbo; margin incurved in youth, then decurved to level, rimulose under dry conditions; surface at first glabrous, becoming silky-fibrillose, discoloring reddish-orange with weathering and age; context 2-3 mm thick, white, soft, faintly pinkish when cut; odor spermatic; taste mild.
Gills close, adnexed to notched with a decurrent tooth, sometimes continuing as lines on the stipe apex; gills pallid in youth, maturing dingy-brown, 4-8 mm broad, occasionally flushed reddish-orange; edges minutely fringed (use hand lens), lighter than the faces; lamellulae in three to four series.
Stipe 2.0-4.0 (6.0) cm long, 0.5- 0.8 (1.0) cm thick, equal to swollen at the base, round, solid, occasionally with a narrow void at the apex; surface cream-colored, the upper third pruinose, the lower portion faintly striate to infrequently finely scaled, discoloring like the cap, reddish to reddish-orange; context cream-colored, faintly pink when cut; partial veil cortinate, the annulus absent or consisting of a thin fibrillose zone midway on the stipe.
Spores 7.5-10.0 x 4.5-5.0 µm , smooth, thin-walled, elliptical in face-view, inequilateral with a flattened and curved side in profile; hilar appendage inconspicuous; spores dull-brown in deposit.
On soil, scattered to gregarious under conifers, infrequently with hardwoods; fruiting from after the fall rains to mid-winter; occasional.
Poisonous, contains the toxin muscarine.
The common name "Blushing Inocybe" aptly describes this Inocybe, but it isn't the only white Inocybe that reddens with age. It belongs to a taxonomically tangled group of species which includes Inocybe pudica, I. armeniaca, and I. godeyi. According to Inocybe expert Dr. Brandon Matheny, Inocybe armeniaca (= I. whitei f. armeniaca (Huijsman) Kuyper), is smaller than I. pudica (=I. whitei B. & Br. ( Sacc.) f. whitei sensu Kuyper), the cap less than 2.5 cm broad, compared to up to 4 cm for the latter, and occurs commonly with cottonwood (Populus spp.) as opposed to mostly with conifers. Complicating matters, Inocybe armeniaca and Inocybe pudica are considered variants of singly morphological species in Europe. Lacking taxonomic accord, the species epithet I. pudica, a name familiar to many users, is used here. Besides the above taxa, another pallid Inocybe that reddens is I. godeyi. It differs from Inocybe pudica in possessing a more fibrillose, slightly ochre-colored cap, a stipe that is pruinose over its entire length, the base more bulbous and often marginate, and a preference for hardwoods.
Ammirati, J.F., Traquair, J.A. & Horgen, P.A. (1985). Poisonous Mushrooms of the Northern United States and Canada. University of Minnesota Press: Minneapolis, MN. 396 p.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Grund, D.W. & Stuntz, D.E. (1981). Nova Scotian Inocybes. VI. Mycologia 73(4): 655-674.
Kuyper, T.W. (1986). A Revision of the Genus Inocybe in Europe. I. Subgenus Insperma and the Smooth-Spored Species of Subgenus Inocybe. Rijksherbarium: Leiden, Netherlands. 247 p.
Nishida, F.H. (1987). The Genus Inocybe in Southern California (Agaricales, Basidiomycetes). Masters Thesis. California State University, Los Angeles: Los Angeles, CA. 315 p.
Stangl, J. (2011). The Genus Inocybe in Bavaria. NuAge Print and Copy: Burnley, UK. 344 p.