Cystodermella cinnabarina

Description

Cystodermella cinnabarina is a basidiomycete fungus of the genus Cystodermella. Its fruiting body is a small agaric bearing a distinctive reddish-colored grainy cap. It occurs in coniferous and deciduous forests throughout the world.

This mushroom has been variously described as inedible, though harmless, and even edible regionally, for example, in Hong Kong.

Mushroom Identification

1. Ecology

   Saprobic; growing alone, gregariously, or in loose clusters under conifers and occasionally under hardwoods (sometimes fruiting from well-rotted wood); summer and fall; widely distributed in North America.

2. Cap

   3-8 cm; dry; egg-shaped or convex at first, becoming broadly convex, broadly bell-shaped, or nearly flat; covered with mealy, granular scales; cinnabar red to orange or rusty cinnamon.

3. Gills

   Attached to the stem but pulling away from it by maturity; close or crowded; white; at first covered by the partial veil.

4. Stem

   3-6 cm long; up to 1.5 cm thick; more or less club-shaped; dry; smooth and whitish to pale cinnamon near the apex, but sheathed with cinnabar granular scales from the base upwards, the sheath terminating in a flimsy ring zone; the granules often wearing away as the mushroom matures, exposing a coarse, whitish surface below.

5. Flesh

   Whitish.

6. Odor and Taste

   Taste mild, slightly oily, or mealy; odor similar.

7. Chemical Reactions

   KOH on cap surface dark purple to black.

8. Spore Print

   White.

9. Microscopic Features

   Spores 4-5 x 2.5-3 µ; elliptical; smooth; inamyloid. Cheilocystidia elongated fusoid-ventricose; 30-46 x 5-9 µ; often apically encrusted. Pleurocystidia absent, or present and comparable to cheilocystidia. Pileipellis elements with rusty brown walls in KOH; chained together; variously sized and shaped. The presence of cystidia is the best character separating Cystoderma cinnabarinum from orangish forms of Cystoderma granulosum.

10. Similar Species

    Cystoderma species can be similar but have amyloid spores and lack cheilocystidia.

History

The species was first described as Agaricus granulosus var. cinnabarinus by German botanist Johannes Baptista von Albertini and the American Lewis David de Schweinitz in 1805. The species has also been known variously as Agaricus terreyi (Berkeley and Broome, 1870), Armillaria cinnabarina (Kauffman, 1922), Lepiota cinnabarina (Karsten, 1914), and Cystoderma terreyi (Harmaja, 1978).

Photo sources:

Photo 1 - Author: Jerzy Opioła (CC BY-SA 4.0)

Photo 2 - Author: Jerzy Opioła (CC BY-SA 4.0)

Photo 3 - Author: Jerzy Opioła (CC BY-SA 4.0)

Photo 4 - Author: Jerzy Opioła (CC BY-SA 4.0)

Photo 5 - Author: damon brunette (damonbrunette) (CC BY-SA 3.0)