''Cyanoboletus pulverulentus'', commonly known as the ink stain bolete, is a species of bolete mushroom. All parts of the mushroom will stain dark bluish-black after handling. It is found in deciduous forest, deciduous and mixed forests, particularly on moist soil on slopes and under beech and oak trees. A common species, it is found in northern Asia, Europe, North Africa, Central and northern South America, and eastern North America. The mushroom hyperaccumulates arsenic and therefore its Edible mushroom, consumption should be limited.

Taxonomy

''Boletus pulverulentus'' was first species description, described by German mycologist Wilhelm Opatowski in 1836. The botanical name, specific epithet ''pulverulentus'' means "covered with powder" and refers to the somewhat dry powdery surface of the young pileus (mycology), cap and stipe (mycology), stalk. The fungus was transferred to the newly created genus ''Cyanoboletus'' in 2014, where it is the type species. Based on the 28S rDNA, North American collection of this fungus reported in the Genbank database (accession numbe
KF030313
does not match that from Europe.

Description

The cap is convex, flat when old, dark reddish-brown becoming lighter with age, and grows up to in diameter. The cap cuticle comprises a tissue layer of undifferentiated hyphae measuring 3–7 μm wide. The stalk is long and slender, bright yellow to orange yellow at the top, and reddish-brown at the base. The flesh is yellow, with a mild taste and immediately turns blackish-blue when handled. The basidia (spore-bearing cells) measure 22–35 by 6–9 μm. Basidiospore, Spores are smooth, fusoid (fuse shaped) to elliptical, and measure 11–15 by 4–6 μm. The spore print colour is olive brown.

Similar species

The eastern North American lookalike ''Boletus oliveisporus'' can be distinguished from ''C. pulverulentus'' by the pink to reddish colour in the center section of its stipe. ''Caloboletus'', ''Lanmaoa'', and ''Xerocomellus'' species may be similar.

Habitat and distribution

An ectomycorrhizal species, ''C. pulverulentus'' forms associations with coniferous and deciduous trees, particularly oak. Fruit bodies appear on the ground, usually singly, in woodland. The bolete is widely distributed, having been reported from northern Asia, Europe, North Africa, Central and northern South America, and eastern North America (from July to September). Reports of appearances in western North American could refer to the similar ''Cyanoboletus rainsii'', which stains greenish-black instead of bluish-black.

Toxicity

A recent study has revealed this mushroom hyperaccumulates arsenic and therefore its consumption should be limited.

Uses

The mushrooms are edible mushroom, edible, but not particularly desirable.

References

External links

{{Taxonbar, from=Q41596453 Boletaceae Edible fungi Fungi described in 1836 Fungi of Africa Fungi of Asia Fungi of Central America Fungi of Europe Fungi of South America Fungus species