Cortinarius praestans - Goliath Webcap

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

Cortinarius praestans usually appears in small groups or singly, in broadleaf and conifer woodland on alkaline soil. This is a rare find in Britain but more common in some parts of mainland Europe, where 'the brave' consider it to be a good edible mushroom. The difficulty of identifying Cortinarius fungi with complete certainty makes this a very risky menu item, and its rarity in most countries is further justification for leaving fruitbodies to drop spores rather than gathering them to eat.

The fine specimens shown on this page were photographed in Roudsea Wood, Cumbria, by Rob Petley-Jones and are displayed here with his kind permission.

Identification guide

	Cap With a sticky or slimy surface, foxy brown sometimes with whitish patches and violaceous tints, the hemispherical or convex cap has a narrowly inrolled margin even when fully mature; the cap surface is often radially wrinkled and the rim slightly or sometimes markedly wavy. Cap diameter is typically 8 to 20cm when fully expanded.
	Gills The adnate gills, which are covered by a cortina in young specimens, are white or pale grey at first, becoming clay brown as the spores mature.
Stem	The fibrilose stem, which is white with violaceous tints, is typically 2 to 5cm in diameter and 8 to 18 cm tall; the base is swollen and may be either clavate or bulbous.
Spore print	Rusty reddish-brown.
Odour/taste	Not distinctive.
Habitat	Under deciduous broadleaf trees and, less frequently, coniferous trees in chalk or limestone areas.
Season	August to November.
Occurrence	Rare.