What You Should Know
Cortinarius cinnamomeus is a basidiomycete mushroom of the genus Cortinarius. This orange fungus produces brown fruit bodies with caps up to 6 cm (2.4 in) wide and stems up to 12 cm (4.7 in) long. The closely crowded gills underside the cap is initially yellow before turning brown. It is common in damp places in coniferous forests. This mycorrhizal woodland mushroom is found mainly in areas of acid soil and often in scattered groups rather than singly.
This mushroom is generally regarded as 'suspect' and may contain dangerous toxins; it should not be gathered for eating. Some reddish Cortinarius species with which the Girdled Webcap could be confused contain the toxin orellanine, which if eaten destroys human kidneys and liver.
Other names: Cinnamon Cort, Cinnamon Webcap.
Cortinarius cinnamomeus Mushroom Identification
Mycorrhizal with conifers, especially pines; growing scattered or gregariously, often in wet areas or with sphagnum; fall (and winter on the West Coast); widely distributed in North America but more common in the Northeast.
1.5-6 cm; convex or nearly conical at first, becoming broadly convex, flat, depressed, or broadly bell-shaped; fairly dry; silky to finely scaly; yellowish or orangish at first, often with olive tones, becoming orangish brown to cinnamon brown overall.
Attached to the stem but sometimes pulling away from it in age; close; orange at first, becoming cinnamon to rusty; covered by a yellowish to orangish cortina when young.
2-12 cm long; up to 1 cm thick; more or less equal; dry; silky with orangish to yellowish (later cinnamon) fibers; yellowish, often discoloring olive-brown to brownish below; sometimes with a rusty ring zone.
Yellowish or olive.
KOH on cap surface red or reddish black.
Spores 6-7.5 x 4-4.5 µ; ellipsoid; moderately roughened. Cheilo- and pleurocystidia absent, but inconspicuous marginal cells present on gill edges. Pileipellis a cutis. Contextual and lamellar elements pinkish purple to purplish in KOH.
Cortinarius semisanguineus has a similar cap and stem but is readily distinguished by its bright red gills.
Cortinarius cinnamomeus Taxonomy and Etymology
When Carl Linnaeus described this webcap mushroom in 1753 he gave it the binomial name Agaricus cinnamomeus, which was later ratified by the great Swedish mycologist Elias Magnus Fries. It was British mycologist Samuel Frederick Gray (1766 - 1828) who in 1821 transferred this species to the genus Cortinarius, thereby establishing its currently accepted scientific name as Cortinarius cinnamomeus.
Synonyms of Cortinarius cinnamomeus include Agaricus cinnamomeus L., Dermocybe cinnamomea (L.) Wünsche, Flammula cinnamomea (L.) P. Kumm., and Gomphos cinnamomeus (L.) Kuntze.
You may also come across this species listed in older field guides as Dermocybe cinnamomea (Schaeff.: Fr.) M.M. Moser.
The generic name Cortinarius is a reference to the partial veil or cortina (meaning a curtain) that covers the gills when caps are immature. In the genus Cortinarius most species produce partial veils in the form of a fine web of radial fibers connecting the stem to the rim of the cap rather than a solid membrane.
The specific epithet cinnamomeus is a reference to the cinnamon color of this mushroom.
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Photo 3 - Author: Jerzy Opioła (Creative Commons Attribution-Share Alike 4.0 International)
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