Xerocomus_chrysenteron

Description: Medium sized boletes (103mm high), solitary to scattered, amongst grass, on soil close to Quercus and a Russula sp.
Pileus: Convex to broadly convex, smooth in young specimens but with large cracks on ageing, brown in colour, dry; diameter 50-72mm.
Stipe: Solid, thicker near cap then straight but tapering again near the base, fibrillose and tearing, yellow near cap with a reddish brown colour in the middle and discolouring towards the base, 13 - 26mm diameter.
Pores: Angular, very variable in size, 13mm high, distant from stipe.
Flesh: Lemon-yellow without colour changes on cutting or bruising except on lower parts of stipe which changes to a brown colour slowly.
Colour tests: Ammonia (10%) and KOH (10%) stipe base changes to brown.

Microscopy:
Basidia: 4-spored.
Cystidia: Fusiform.
Spores: Elongated, smooth, 12.1-16.2µm x 5.0-6.5µm, Q=2.23-2.91, Qm=2.53

The 'typical' X. chrysenteron is reported to change colour to blue but this has not been observed in any of the specimens. A specimen similar to this species has been reported on Boris Assyov's site.