''Cortinarius traganus'', also known as the gassy webcap or lilac conifer cortinarius, is a basidiomycete mushroom of the genus '' Cortinarius''. The mushrooms are characterized by their lilac color, the rusty-brown gills and

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, f ...

s, and rusty-brown flesh in the

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

Taxonomy

The species was originally named ''Agaricus traganus'' by

Elias Magnus Fries Elias Magnus Fries (15 August 1794 – 8 February 1878) was a Swedish mycologist and botanist. Career Fries was born at Femsjö (Hylte Municipality), Småland, the son of the pastor there. He attended school in Växjö. He acquired ...

. It is commonly known as the "gassy webcap" the "lilac conifer Cortinarius", or the "pungent Cort". Some authorities consider the American variant to be a distinct species, ''Cortinarius pyriodorus'', reserving the name ''C. traganus'' for the European version.

Description

The cap is in diameter, initially spherical to convex, with the margin rolled inward, then flattened, sometimes with large, broad, central umbo. The margin often cracks star-like, particularly in dry weather. The mushroom is a pale azure violet to pale lilac color, soon bleaching and fading to tan brown or rusty brown. The cap is dry, silkily shiny or tomentose at the margin with membranaceous bronze fragments of the veil, the white fragments of which often adhere to the surface like scabs. Later the surface becomes cracked into small scales. The gills are sub-crowded, quite thick, broadly adnate, and often slightly emarginate (notched). They are broad, slightly dirty violet when young but usually brown, with only faintly violet tint, later brown, dusted saffron ochre, and with lighter crenulate edge. The

is long and thick, tough and thick, bulbously at the base, and spongily stuffed inside. It is vivid violet for a long time in the upper part above the cortina, paler below, and covered with a tough, whitish, boot-like veil, which usually leaves upright zones on the stem. The cortina is violet. The flesh is saffron yellowish-brown to yellowish-brown from the beginning except at the tip of the stem where it is dirty violaceous, or, unpleasantly, goats, so much so that it may induce vomiting in more sensitive individuals. It has a strong, bitter taste, particularly when young. The basidia (the

-bearing cells) are 30–35 by 6.5–7.5

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

. The

spore deposit 300px, Making a spore print of the mushroom ''Volvariella volvacea'' shown in composite: (photo lower half) mushroom cap laid on white and dark paper; (photo upper half) cap removed after 24 hours showing pinkish-tan spore print. A 3.5-centimeter ...

is rusty brown. The spores are

ellipsoid An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...

, covered with fine warts or dots, and measure 8–9 by 5–5.5 μm.

Similar species

'' Cortinarius camphoratus'' is similar in appearance and is also violet, but it has pale violet gills which soon turn rusty, and a longer stem with paling flesh at the base. Its spores are also longer, warty, and measure 8.5–11 by 5–6 μm. It has a pungent smell, somewhat different from that of ''C. traganus''—similar to rotting potatoes. Another lookalike species is '' Cortinarius muricinus'' with the cap either permanently violet or becoming rust-colored from the disc outward. The gills are initially blue, dirty cinnamon when old, and the stem violet lilac, with lighter fragments of the veil later turning rust-colored. Its spores measure 13–15 by 7–8 μm.

Edibility

The mushroom has been variously reported as "mildly poisonous", or indigestible. It should not be consumed due to its similarity to deadly poisonous species.

Distribution and habitat

''Cortinarius traganus'' is a widespread species that is found in coniferous forests worldwide. It seems to prefer poorer soils, both siliceous and non- calcareous. It grows throughout the temperate zone of the northern hemisphere.

References