Violet-grey bolete

Appearance

The cap of the fruit body is 7 to 15 c in diameter, initially convex in shape but becoming centrally depressed, with a broadly arched and rounded margin. Young specimens are rather hard and firm, and the cap has a finely velvet-textured surface that soon wears off to become smooth. The color of the fruit body is violet when young, but dulls as it ages, becoming a dull violet-purplish-gray, then eventually chocolate-brown at maturity. The flesh is solid, white, and does not change color when cut or bruised. The taste is bitter, and the odor is not distinctive. Mycologist David Arora calls the mushroom "beautiful, but bitter-tasting".

The tubes on the underside of the cap are 0.4 to 1.8 cm deep, 2 or three per millimeter, depressed at the stem . The color of the pore surface is initially white, and it remains so for a while before turning a rosy color at maturity. The stem is 8 to 13 cm long and 2.5 to 4 cm thick, enlarged at the base, and sometimes bulbous. The surface is slightly reticulate at the top, and smooth lower of the stem.

Its color is buff to light brown, often with darker brown bruises or stains, and it has whitish mycelium at the base. The flesh of the stem is white, and it does not change color when cut or bruised.Collected in deposit, like with a spore print, the spores of ''T. plumbeoviolaceus'' appear to be a light pink to flesh color. When viewed with a light microscope, they are elliptical, with smooth walls and dimensions of 9.1–12.3 by 3.4–4.5 µm. The basidia are club-shaped, and measure about 26 by 6.5 µm. The cuticle of the cap is made of a tangle of smooth-walled, narrow, brownish hyphae. When stained in potassium hydroxide, the hyphal contents tend to form beads, while staining in Melzer's reagent causes the pigment to form globules. Cystidia are common in the hymenial tissue; they are swollen at the base and narrow at the apex , measuring 30–40 µm long by 7–9 µm thick. Clamp connections are absent in the hyphae.

Habitat

''Tylopilus plumbeoviolaceous'' is a mycorrhizal species, and the bulk of the fungus lives underground, associating in a mutualistic relationship with the roots of various tree species. The fruit bodies are found growing singly, scattered or clustered together during mid-summer to autumn in deciduous forests, often under beech or oak trees; however, it sometimes occurs in mixed hardwood-conifer forests under hemlock. A preference for sandy soil has been noted in one source. In North America, the mushroom can be found east of the Rocky Mountains, ranging from Canada to Mexico. The species has also been collected in North Korea. Fruit bodies can serve as a food source for fungus-feeding ''Drosophila'' flies.