Boletus chrysenteron - Red Cracking Bolete

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

An untidy bolete when mature, and of little cullinary interest because of its poor texture, Boletus chrysenteron, the Red Cracking Bolete, can be found in summer and autumn. It is now clear that a complex of species was included under the label 'Red Cracking Bolete' - see also Boletus truncatus.

This species (formerly classified as Xerocomus chrysenteron) has been recently moved to the genus Boletus, as have most of the Xerocomus boletes.

Identification guide

Cap	This species is characterised by a shallow, convex grey-yellow or brownish cap that soon crazes to reveal a thin layer of red flesh below the cap skin. 4 to 10cm in diameter when fully expanded, the caps have very little substance and the thin flesh blues very slightly when cut. Young specimens often have dark downy caps and might easily be mistaken for Bay Boletes (Boletus badius).
Tubes and Pores	The yellow tubes terminate in large, angular pores that are lemon yellow at first but turn greenish with age. When bruised, the pores of mature specimens turn dark blue.
Stem	The stem, which has no ring, is bright yellow and the lower part is covered in coral-red fibrils that give it a 'stick of rhubarb' appearance. When cut, the cream stem flesh turns blue near the base of the stem. 10 to 15mm in diameter and 4 to 8cm tall, the stem is more or less constant in diameter throughout its length.
Spore print	Olivaceous brown.
Odour/taste	Not distinctive.
Habitat	This mycorrhizal species is often found beneath hardwoods, notably beech and hazel, but it is also found occasionally in coniferous forests, particularly beside footpaths (where it may be attached to the roots of deciduous trees growing there).
Season	mainly in August to November, but occasionaly much earlier in the year.
Occurrence	Very common.
Similar species	Pseudoboletus parasiticus (syn. Xerocomus parasiticus and Boletus parasiticus) has a yellow stem without red fibrils, and it occurs only with the Common Earthball (Scleroderma citrinum) upon which it may be slightly parasitic.