What You Should Know
Cortinarius caerulescens is a very frequent mushroom at the peak of the season in the evergreen oak woods of Montserrat and Mura. The cap is shiny violet color and convex shape when young, but it opens to flat and turns to ocher from the center while aging. The full flat cap measures from 6 to 20 cm diameter and displays dull ocher color with just a slight violet shade remaining on the border. The grills also begin bluishly and turn to ocher. The stipe is white. It blows at the bottom, especially in young individuals.
This mushroom is reported by some authorities to be 'edible but worthless', whereas in other field guides it is recorded as 'suspect'.
Other species of Cortinarius are close to C.caerulescens . Amongst the common ones, there are C.purpurascens with a violet stipe, C.calochrous smaller, with a reddish shade and a big bulb in the stipe, and C.elegantissimus with sulfur yellow color.
Other names: Mealy Bigfoot Webcap.
Cortinarius caerulescens Mushroom Identification
Young caps are convex, later flattening as they expand but invariably retaining an in-rolled margin even when fully developed. The cap diameter varies from 6 to 20 cm at maturity. At first a beautiful blue-mauve and particularly fibrillose at the margin, the cap turns ochre-brown, or sometimes rufous-brown, from the center and becomes more smooth and shiny with age. In dry weather the margin wrinkles, whereas in wetter conditions it tends to remain more regularly circular.
The adnate to notched gills are toothed and are close and initially white or pale grey and covered by a fleeting bluish cortina. As the spores mature, the gills turn rusty brown, but they usually retain a pale edge until the fruitbody begins decaying.
The stipe is white at first and clavate (club-shaped), broadest at the base, becoming more parallel-sided as the cap expands. It is covered with long flaky scales below a fleeting ring formed as the cortina parts.
Amygdaloid, verrucose, 8.5-10 x 5-5.5Îµm; dextrinoid.
Odor and Taste
Odor slightly earthy; taste mild.
Habitat & Ecological Role
In deciduous woodland in chalk and limestone areas, infrequent in warm and sheltered locations and rare elsewhere.
Cortinarius caerulescens Look-Alikes
Has a darker violet cap, gills and stem, and its flesh is deep violet throughout.
Has a deep purple cap, although it also wears a silver cap. There are bigger disputes.
Has a unique bright blue hat.
Has a silvery-blue cap and is found in coniferous forests.
Has a purple cap with many round spots. It has an eloquent pink-red reaction with a potassium base.
Cortinarius caerulescens Taxonomy and Etymology
When in 1762 Jacob Christian Schaeffer described this woodland mushroom he gave it the binomial name Agaricus caerulescens.
In 1838 the Swedish mycologist Elias Magnus Fries transferred this species to the genus Cortinarius, whereupon its scientific name became Cortinarius caerulescens. This webcap is a member of the Cortinarius subgenus Phlegmaceum.
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.
Counter-intuitively, the specific epithet caerulescens could be translated as 'becoming blue', whereas the cap surface of the Mealy Bigfoot Webcap starts off blue and becomes brown as the fruitbody ages; however, another meaning of the suffix -escens is 'almost'. Almost blue is therefore the more appropriate interpretation in this instance.
Cortinarius caerulescens Synonyms
Agaricus caerulescens Schaeff.
Agaricus cyanus var. caerulescens (Schaeff.) Pers.
Cortinarius caesiocyaneus Britzelm
Cortinarius cyanus var. caerulescens (Schaeff.) Gray, 1821
Phlegmacium caerulescens (Fr.) Wünsche, 1877
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