Cortinarius semisanguineus

Description

Cortinarius semisanguineus (syn. Dermocybe semisanguineu) is a medium-sized mushroom with a pale brown to an ochre cap, and bright blood-red gills, and a yellowish stem. It grows typically with conifers and birch. Cortinarius is a very large genus of mycorrhizal mushrooms, with over 400 described species. Determining the correct species is considered to be very difficult.

This mushroom can be used to produce a beautiful brown-orange dye. In Nordic countries, this abundant mushroom was traditionally used to produce colored wool like the sample of dyed yarn shown above.

Common names: Poison Dye Cort, Surprise Webcap.

Mushroom Identification

1. Ecology

   Mycorrhizal with conifers, especially pines; growing alone or scattered, often in moss; summer and fall; widely distributed in North America.

2. Cap

   1.5-7 cm; more or less convex at first, becoming broadly convex, flat, or broadly bell-shaped, sometimes with a sharp central bump; dry; silky; yellowish-brown to cinnamon brown, often darker over the center.

3. Gills

   Attached to the stem but often pulling away from it in age; close; blood red, becoming cinnamon to rusty; covered by a yellowish cortina when young.

4. Stem

   2.5-10 cm long; up to 1.5 cm thick at the apex; more or less equal; dry; silky; usually pale yellowish, but often darker or reddish toward the base; often with a rusty ring zone.

5. Flesh

   Whitish or pale yellowish.

6. Odor

   Mild or radishlike.

7. Chemical Reactions

   KOH on cap surface purple to purplish black.

8. Spore Print

   Rusty brown.

9. Microscopic Features

   Spores 6-9 x 4-5 µ; ellipsoid; slightly roughened. Cheilo- and pleurocystidia absent. Pileipellis a cutis. Contextual and lamellar elements pinkish purple to purplish in KOH.

History

This webcap was described in 1821 by the great Swedish mycologist Elias Magnus Fries, who gave it the name Agaricus cinnamomeus a semisanguineus and so established its basionym - the base name of its specific epithet. It was the French mycologist Claude-Casimir Gillet (1806 - 1896) who transferred this species to its current genus, thereby renaming it Cortinarius semisanguineus.

Synonyms of Cortinarius semisanguineus include Agaricus cinnamomeus a semisanguineus Fr., Cortinarius cinnamomeus ß semisanguineus (Fr.) Sacc., and Dermocybe semisanguinea (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 blood-red color of the gills contrasting with the much paler color of the cap is the basis of the specific epithet semisanguineus, which comes from Latin and simply means 'half-blood red'.

Photo sources:

Photo 1 - Author: Jimmie Veitch (jimmiev) (CC BY-SA 3.0)

Photo 2 - Author: wearethechampignons (CC BY-SA 4.0)

Photo 3 - Author: wearethechampignons (CC BY-SA 4.0)

Photo 4 - Author: User:Strobilomyces (CC BY-SA 2.5)

Photo 5 - Author: Jason Hollinger (CC BY-SA 2.0)