Imperator torosus

1. Imperator torosus

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Imperator torosus, the brawny bolete, is a fungus in the family Boletaceae. Native to southern Europe, the Caucasus and Israel, it is generally associated with deciduous trees such as hornbeam, oak and beech in warm, dry locales. Although generally rare in Europe, it appears to be relatively common in Hungary. Appearing in summer and autumn on chalkysoils, the stocky mushrooms have an ochre capup to 20 cm (8 in) across, yellow pores on the cap underside, and a wine-red to brown or blackish stalk up to 6–15 cm (2.4–5.9 in) long by 3–6 cm (1.2–2.4 in) wide. The pale yellow flesh changes colour when broken or bruised depending on age; younger mushrooms become reddish, and older ones take on bluish tones. Swedish mycologists Elias Magnus Fries and Christopher Theodor Hök described this species as Boletus torosus in 1835, relying in part on the work of Louis Secretan. Eating raw, or sometimes even cooked, mushrooms of this species leads to vomiting and diarrheaImperator torosus, commonly known as the brawny bolete, is a species of bolete fungus in the family Boletaceae. It is native to southern Europe east to the Caucasus and Israel. It is generally associated with deciduous trees such as hornbeam, oak and beech in warm, dry locales. Although generally rare in Europe, it appears to be relatively common in Hungary. Appearing in summer and autumn on chalky soils, the stocky fruit bodies have an ochre cap up to 20 cm (8 in) across, yellow pores on the cap underside, and a wine-red to brown or blackish stipe up to 6–15 cm (2.4–5.9 in) long by 3–6 cm (1.2–2.4 in) wide. The pale yellow flesh changes to different colours when broken or bruised depending on age; younger mushrooms become reddish, and older ones additionally take on bluish tones.

Imperator torosus
Scientific classification
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Boletales
Family:	Boletaceae
Genus:	Imperator
Species:	I. torosus
Binomial name
Imperator torosus (Fr.) Assyov, Bellanger, Bertéa, Courtec., Koller, Loizides, G.Marques, J.A.Muñoz, N.Oppicelli, D.Puddu, F.Rich. & P.-A.Moreau (2015)
Synonyms[1][2]
Boletus torosus Fr. (1835) Dictyopus torosus (Fr.) Quél. (1886) Boletus purpureus var. xanthocyaneusRomagn. (1948) Boletus xanthocyaneus (Ramain) Romagn. (1976)

Imperator torosus
Mycological characteristics
	pores on hymenium
	cap is convex or flat
	stipe is bare
	spore print is olive-brown
	ecology is mycorrhizal
	edibility: poisonous

Elias Magnus Fries and Christopher Theodor Hök first described this species as Boletus torosus in 1835, a name by which it came to be known for many years. Modern molecular phylogeneticsshows that it is only distantly related to Boletus edulis—the type species of Boletus—and it was duly placed in the new genus Imperator in 2015.

Eating raw mushrooms of this species leads to vomiting and diarrhea. Gastrointestinal symptoms have also occurred after eating cooked specimens, though some people have eaten it without ill-effects.