Gray-blue webcap (Cortinarius caerulescens) photo and description

Gray-blue webcap (Cortinarius caerulescens)

  • Department: Basidiomycota (Basidiomycetes)
  • Subdivision: Agaricomycotina (Agaricomycetes)
  • Class: Agaricomycetes (Agaricomycetes)
  • Subclass: Agaricomycetidae (Agaricomycetes)
  • Order: Agaricales (Agaric or Lamellar)
  • Family: Cortinariaceae (Spiderwebs)
  • Genus: Cortinarius (Webcap)
  • Species: Cortinarius caerulescens (gray-blue webcap)

This type of mushroom has several Russian and Latin synonyms:

  • The webcap is blue;

  • The webcap is blue;

  • The webcap is watery blue;

  • The webcap is bluish;

  • Phlegmacium caerulescens;

  • Cortinarius cumatilis

  • Cortinarius cyanus.

Gray-blue webcap (Cortinarius caerulescens)

The gray-blue webcap (Cortinarius caerulescens) belongs to the Spiderweb family, is a representative of the Spiderweb genus.

External description

The gray-blue webcap (Cortinarius caerulescens) is a large mushroom, consisting of a cap and a leg, with a lamellar hymenophore. There is a residual blanket on its surface. The diameter of the cap in adult mushrooms is from 5 to 10 cm, in immature mushrooms it has a hemispherical shape, which then becomes flat and convex. When dry, it becomes fibrous, mucous to the touch. In young cobwebs, the surface is characterized by a blue tint, gradually becomes light-ocher, but at the same time a bluish border is preserved along its edge.

The fungal hymenophore is represented by a lamellar type, consists of flat elements - plates attached to the stem with a notch. In young fruiting bodies of fungi of this type, the plates have a bluish tint, with age they darken, becoming brownish.

The length of the leg of the gray-blue spider web is 4-6 cm, and the thickness is from 1.25 to 2.5 cm.At its base there is a tuber-like thickening visible to the eye. The surface of the leg at the base has an ocher-yellow color, and in the rest of it is bluish-purple.

The mushroom pulp is characterized by an unpleasant aroma, gray-blue color and insipid taste. The spore powder has a rusty brown color. The spores included in its composition are characterized by dimensions of 8-12 * 5-6.5 microns. They are almond-shaped, and the surface is covered with warts.

Season and habitat

The bluish-blue spider web is widespread in North America and in the countries of the European continent. The fungus grows in large groups and colonies, is found in mixed and broad-leaved forests, is a mycorrhiza-forming agent with many deciduous trees, including beech. On the territory of Russia, it is found only in the Primorsky Territory. Forms mycorrhiza with various deciduous trees (including oak and beech).


Despite the fact that the mushroom belongs to the category of rare, and you can see it infrequently, it is ranked as edible.

Similar types and differences from them

Some scientists distinguish the name watery-blue cobweb (Cortinarius cumatilis) in a separate species. Its distinctive feature is a uniformly colored bluish-gray cap. Tuberous thickening is absent in it, as well as the remains of the bedspread.

The described type of mushroom has several similar types:

Mayor's Webcap (Cortinarius mairei). It is distinguished by white plates of the hymenophore.

Cortinarius terpsichores and Cortinarius cyaneus. These varieties of mushrooms differ from the gray-blue spider web by the presence of radial fibers on the surface of the cap, a darker color, and the presence of remnants of the blanket on the cap, which disappear over time.

Cortinarius volvatus. This type of mushroom is characterized by a very small size, a characteristic dark blue color. It grows mainly under coniferous trees.