Cortinarius triumphans, also known as the birch webcap, or yellow girdled webcap is a basidiomycete mushroom

Mushroom

A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...

 of the genus Cortinarius

Cortinarius

Cortinarius is a genus of mushrooms. It is suspected to be the largest genus of agarics, containing over 2000 different species and found worldwide. A common feature among all species in the genus Cortinarius is that young specimens have a cortina between the cap and the stem, hence the name,...

found in Europe. It is regarded as edible by some authorities, although others call it suspect and it resembles inedible species.

Taxonomy

The species was first described by Swedish mycologist Elias Magnus Fries

Elias Magnus Fries

-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...

 in 1838; its generic name derived from the Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 cortina "veil", and the specific triumphans "triumphing". It is considered the same species as Cortinarius crocolitus Quélet by some authorities. It is a member of the subgenus Phlegmacium within the genus Cortinarius

Cortinarius

Cortinarius is a genus of mushrooms. It is suspected to be the largest genus of agarics, containing over 2000 different species and found worldwide. A common feature among all species in the genus Cortinarius is that young specimens have a cortina between the cap and the stem, hence the name,...

; mushrooms of this group have sticky (or slimy in wet weather) caps and dry stipes.

Description

It has a 5–12 cm (2–5 in) diameter cap

Pileus (mycology)

The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...

 which is yellowish in colour-darker in the centre and paler on the edges. The stipe

Stipe (mycology)

thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...

 is 7–17 cm (3–7 in) high and 1–2.5 cm (0.4–1 in) thick and swollen at the base, and is white up top and yellow lower down and bears the tan or brown remnants of the veil. The adnate gills, which are hidden by a cream or white veil when young, are cream or lilac early on, and darken with the spores, which give a rusty coloured spore print

Spore print

thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...

. The almond-shaped spores measure 10–12.5 × 5.5–7 µm

Micrometre

A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...

. The flesh is cream-coloured and the taste mild.

Distribution and habitat

Cortinarius triumphans appears under birch

Birch

Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...

 trees in autumn (fall) in Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, and Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

 where it is widespread, but local. It is also reported from north eastern North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. It has a mycorrhizal relationship with birch trees (Betula).

Edibility

Although some mushroom guides list it as edible, others treat it with suspicion, as many webcaps have been found to have toxins, not in the least the similarly brown-coloured lethal webcaps. This being the case, it is probably best to avoid it. Thomas Laessoe's 1998 book 'Mushrooms', describes the taste as bitter, with a not unpleasant smell.