Cortinarius umbrinolens

Cap 1.5 to 4 cm across, conical then expanded and umbonate, dark brown when moist, especially at the centre, drying yellow brown, surface silky matt, with a pale edge. It has a characteristic earthy smell like beetroot (with a hint of rhubarb). 

Habitat damp places with deciduous trees, and often with birch.

Autumn.

Widespread but infrequent in Britain.

Infrequent in Leicestershire and Rutland.