**Taxonomy and Classification:**
– Pierre Bulliard described B.edulis in 1782.
– Boletus edulis is the type species of the genus Boletus.
– Rolf Singer’s classification places B.edulis as the type species of section Boletus.
– Molecular analysis in 1997 established Boletales as a separate order.
– The generic name derives from the Latin term for mushroom.
**Common Names and Cultural Significance:**
– Common names for B.edulis vary by region.
– Italian name porcino means porcine.
– English name penny bun refers to its shape.
– German name Steinpilz refers to its firm flesh.
– French King Charles XIV John popularized B.edulis in Sweden.
**Description and Morphology:**
– Cap of B.edulis is 7–30cm broad at maturity.
– Stipe is club-shaped and finely reticulate on the upper portion.
– Under surface of the cap is made of thin tubes.
– Pores are whitish when young, maturing to greenish-yellow.
– Cap color is reddish-brown fading to white near the margin.
– Pores are small, roughly 2 to 3 pores per millimeter.
– Pores are white in youth, changing to yellow and then brown with age.
– Spore print is olive brown.
– Flesh is white, thick, and firm when young, becoming spongy with age.
– Fully mature specimens can weigh about 1kg (2lb 3oz).
**Distribution and Habitat:**
– B.edulis is widely distributed in the Northern Hemisphere.
– It does not occur naturally in the Southern Hemisphere.
– Introduced to southern Africa, Australia, New Zealand, and Brazil.
– Western North American variant identified in 2007.
– Grows in deciduous and coniferous forests forming mycorrhizal associations.
– Found in areas dominated by pine, spruce, hemlock, and fir trees.
– Also found in forests with chestnut, beech, and oak trees.
– Can grow up to an altitude of 3,500m (11,500ft).
– Common in scrublands in northwestern Spain.
– Especially favored in the Midi region of south-west France.
**Culinary Use and Commercial Importance:**
– B.edulis is prized in culinary dishes.
– Low in fat and digestible carbohydrates.
– High in protein, vitamins, minerals, and dietary fiber.
– Difficult to cultivate commercially.
– Sold fresh in autumn, often dried and distributed worldwide.
– Boletus edulis var. grandedulis is more highly regarded by gourmets.
– California king bolete can reach massive proportions.
– Queen bolete is smaller and typically found in mixed forests.
– Spring king bolete fruits in clusters and appears in the spring.
– Boletus rex-veris is found throughout western North America.