Xerocomus pruinatus (now more commonly accepted as Xerocomellus pruinatus) is a species of mushroom in the family Boletaceae, native to Europe. It is commonly known as the matte bolete (or powdery bolete).
Taxonomy
The species was originally described as Boletus pruinatus by Elias Magnus Fries and Fredrik Christopher Theodor Hök in 1835. It was later transferred to the genus Xerocomus by French mycologist Lucien Quélet, and then moved to the genus Xerocomellus by Czech mycologist Josef Šutara in 2008, based on morphological and DNA studies. The currently accepted scientific name is Xerocomellus pruinatus (Fr. & Hök) Šutara (2008).
Etymology
The specific epithet pruinatus means "with a fine bloom" or "frosted," referring to the delicate, frost-like waxy bloom (pruina) that often coats the cap surface, giving it a matte, velvety appearance.
Description
- Cap: 3–10 cm in diameter, hemispherical when young, later convex to flattened. Color ranges from light brown to dark chestnut brown, greyish brown, olivaceous brown, reddish brown, or even almost black. The surface is dry, finely velvety or finely dusted (pruinose), and rarely cracks (unlike the similar Red Cracking Bolete).
- Pores: Large, angular, pale yellow at first, turning blue-green when bruised.
- Stem: Yellow with fine red dots, especially on the central and lower parts. Basal mycelium is yellow.
- Flesh: Firm, pale to bright yellow, slowly turning slightly blue when cut, particularly towards the stem base.
- Spores: Subfusiform (broadly spindle-shaped), smooth, 11.5–14 × 4.5–5.5 µm. Spore print is olivaceous-brown.
Habitat and Distribution
It is found in mixed woodland, particularly under beech trees (Fagus spp.), and shows a marked preference for alkaline (chalky or lime-rich) soils. It is native to Europe, though it is considered quite rare in Britain and Ireland. The fruiting season is typically August to November.
Edibility
Xerocomellus pruinatus is generally considered edible, but it is regarded as a poor-quality mushroom. It is small and not abundant enough to be of significant culinary interest.
Similar Species
It is easily mistaken for the Red Cracking Bolete (Xerocomellus chrysenteron), but the latter's cap develops cracks with age, revealing red flesh beneath, whereas X. pruinatus rarely cracks and shows yellow flesh when it does.
