Lentinus arcularius.
Basidiomycota > Agaricomycetes > Polyporales > Polyporaceae.
There are nearly 30 synonyms including Polyporus arcularius and Boletus arcularius.
It grows on dead wood, solitary or in groups of 2 or 3, and causes white rot.
The mycelium is white.
The stem, up to 4 (6) cm high and 4 mm wide, is at or near the centre of the cap.
It is brown or yellow-brown, hairy or scaly.
The cap is 4 (7-8) cm across, convex, flat or with a shallow central depressoion.
It is pale tan with concentric zones of darker brown or yellow-brown scales and fibrils.
The margin has small hairs, up to 1 mm long, projecting from it.
When dry it is concentrically ridged.
The pores are white then brownish, hexagonal or angular and up to 2 mm long.
The radially arranged pores run onto the stem where they may be longer.
The walls between the pores are slightly incised.
Spore print is creamy white.
J.F.