Matte Bolete

Description

The matte bolete has a cap 3–10 cm across, velvety, dry and evenly reddish brown or dark brown. When touched or damaged it darkens to reddish brown. Underneath are yellow pores, whitish at first, which turn blue when pressed. The stem is hard and yellow, with reddish brown tinges, and always yellow just below the cap.

It grows in coniferous and deciduous forests from September to November, most abundantly after the weather cools. Many localities are known in Poland.

You can tell it from other related boletes by its cap, which does not crack into patches even with age and in dry weather. If you are not sure of the species, do not pick it or eat it.

Identification features

Cap

Diameter 3–10 cm, shape flat-convex or cushion-shaped. Cap surface velvety, dry, uniformly reddish brown or dark brown; damaged spots turn reddish brown. Distinguishing feature: with age and in dry weather the cap does not crack into patches.

Hymenophore (underside of the cap)

Tubes pale ochre in young fruiting bodies, later pale yellow; they turn blue when damaged. Pores whitish at first, later yellow or yellow-green. How the tubes attach to the stem: no data.

Stem

Height 5–10 cm, thickness 1–2 cm, cylindrical, solid and hard. Surface longitudinally fibrous, on a yellow background with reddish brown tinges; always yellow just below the cap. No ring.

Flesh

Yellow, juicy and fairly firm, fibrous in the stem. Turns slightly blue when damaged. Taste fruity, smell pleasant.

Spore print and spores

Spore print brown. Spores smooth, thick-walled, brown or olive-green, somewhat fusiform, without an oil droplet, 11.5–14 × 4.5–5.5 µm. Basidia four-spored.

Habitat and distribution

Ecology. Terrestrial mycorrhizal fungus. Grows in various types of coniferous and deciduous forests. Specific mycorrhizal partners: no data.

Distribution. Reported only from Europe. Many localities are known in Poland. Not legally protected in Poland; it is sometimes suggested as a species worth considering for protection.

Fruiting. From September to November, most abundantly after the weather cools.

What can it be confused with?

• Xerocomellus chrysenteron (suchogrzybek złotopory) — The cap is often cracked into patches, exposing paler flesh; X. pruinatus has a smooth cap that does not crack even with age.
• Xerocomus subtomentosus (Polish: podgrzybek zajączek) — Cap olive-brown, cracking into patches.
• Xerocomus ferrugineus (Polish: podgrzybek grubosiatkowany) — The stem is not as red, the cap is paler and cracks into patches in dry weather.

Never rely on a single feature. If you are not sure — do not pick it; show the mushroom to a qualified mushroom expert.

Interesting facts

• Described in 1835 by Elias Fries and C.T. Hök as Boletus pruinatus; the current genus name Xerocomellus was given to it in 2008 by the Czech mycologist Josef Šutara.
• The English name “matte bolete” refers to the matte, velvety cap.
• The Polish name “suchogrzybek oprószony” was recommended in 2021 by the Commission for Polish Fungal Nomenclature of the Polish Mycological Society; earlier names included borowik oprószony, podgrzybek oprószony and podgrzybek aksamitny.