Cystoderma amianthinum
Description
Cystoderma amianthinum is a small fragile agaric with light brown to a yellowish cap, white or cream gills, and a coarsely granular stem with a ring. It grows summer to fall solitary or scattered in small tufted groups in damp mossy grassland, in coniferous forest clearings, or on wooded heaths. Some forms have a highly wrinkled cap surface; others have white to pale yellow coloration. The gills are white to pale yellowish, the odor is disagreeable or somewhat like freshly husked corn, and the spores are amyloid.
This mushroom is widespread in Europe and North America, and common in northern temperate zones. It occurs in mossy woodland, on heaths, amongst grass or bracken, and sometimes with willow. It is often found in acidic soils.
Cystoderma amianthinum is nonpoisonous, but eating is not advised as the deadly toxic Lepiota castanea is a common look-alike. It is also similar to the inedible Cystoderma fallax.
Common names: Earthy Powdercap, Saffron Parasol.
Mushroom Identification
Ecology
Saprobic; growing alone, scattered, or gregariously, usually in moss under conifers; late summer and fall (overwinter in California); widely distributed in northern and montane North America.
Cap
2-5 cm; dry; convex, obtusely conic, or bell-shaped at first, becoming broadly convex, broadly bell-shaped, or nearly flat; frequently somewhat wrinkled in radial patterns (strikingly so in one version); covered with mealy granules; pale reddish-brown to yellowish brown or yellowish.
Gills
Attached to the stem; close; whitish becoming pale yellowish.
Stem
3-7 cm long; 3-8 mm thick; more or less equal, or tapering to apex; dry; pale and fairly smooth near the apex, but sheathed with granular material and colored like the cap below; the sheath terminating in a flimsy ring that often fragments or disappears.
Flesh
Whitish; thin.
Odor and Taste
Taste mild; odor usually pungent and unpleasant.
Chemical Reactions
KOH on cap surface rusty red.
Spore Print
White.
Microscopic Features
Spores 4-7 x 3-4 µ; elliptical; smooth; at least weakly amyloid. Cystidia absent. Pileipellis elements with rusty brown walls in KOH; chained together; inflated; subglobose.
Similar Species
Squamanita paradoxa, the Powdercap Strangler, is a rare grassland mushroom that attacks the Earthy Powdercap, Cystoderma amianthinum, apparently growing up through its stem and producing a violet cap in place of the orange cap of the Earthy Powdercap. The lower part of the stem remains identical to that of the host mushroom, giving a very strange two-tone effect.
History
When Giovani Antonio Scopoli described this species in 1772 he gave it the scientific name Agaricus amianthinus. In 1889 the Swiss mycologist Victor Fayod (1860 - 1900) transferred the Earthy Powdercap into the genus Cystoderma, creating its currently accepted scientific name Cystoderma amianthinum.
Synonyms of Cystoderma amianthinum include Agaricus amianthinus Scop., Lepiota granulosa var. amianthina (Scop.) P. Kumm., Lepiota amianthina (Scop.) P. Karst., Lepiota amianthina var. alba Maire, and Cystoderma amianthinum f. rugulosoreticulatum Bon.
The generic name Cystoderma means 'blistered skin' - but their most distinctive feature is the marked contrast between the smoothness of the stem above the ring and its scaly surface below.
The specific epithet amianthinum means like amiantus (from a Latin origin) or amiantos (from Greek) and means pure or unsullied.
Photo sources:
Photo 1 - Author: Holger Krisp (CC BY 3.0)
Photo 2 - Author: Ben Deed (CC BY-SA 4.0)
Photo 3 - Author: Jerzy Opioła (CC BY-SA 2.5)
Photo 4 - Author: Angelos Papadimitriou (Aggelos(Xanthi)) (CC BY-SA 3.0)
