Cap: 30-110 mm, convex when young, then plano-convex and irregularly undulating with depressed centre, upper surface tomentose to finely fibrillose-squamose (scaly), ochre- to pink-brown, red-brown when old, margin incurved when young, then undulating and cleft. Lower surface covered with crowded spines up to 5 x 0.5 mm, light pink-brown when young, purple brownish when old, decurrent (running down stem). Stem: 28-60 x 8-25 mm. cylindrical to conical with tapering, almost rooting; base rounded, longitudinally fibrillose, punctate to finely squamose, solid, purple-brown, black-green toward the base, sometimes eccentrically attached. Flesh: when cut immediately light pink-lilac, then darkening to dark violet, eventually fading to dull brown. Flesh of the cap dull greyish-brown under the upper surface, dull grey over the spines, suffused with lilac in the centre. Odour: farinaceous, taste somewhat sharp and biting. Hyphal system: monomitic, subhymenial hyphae inflating, thin-walled, 4-7 µm across, septa without clamps, hyphae in the pileal trama up to 20 µm across. Basidia: slenderly clavate 34-39 x 7-8 μm, 4 spored, without basal clamp. Spores: subglobose, coarsely tuberculate (with bumps) with blunt, sometimes double tubercles, brownish, size including tubercles: 5.4-5.8 (6.3) x (4) 3.6-4.2 (4.5) μm. Cystidia: none.